Reword the recent deobfuscation changes

In most cases the word was changed to 'obfuscation' as it was about
obfuscation, not deobfuscation. In some cases like 1995/leo since the
file was (in 1995/leo) about a secret switch it was changed to
'secret.md' (and 'secret.html') but there were others like that as well.

One entry had the words 'spoiling the size rule' but this had been
changed to 'deobfuscating the size rule' which was obviously wrong.

In the latter YYYY/README.md files the judges had written after some
entries (brief summaries) '...

    ...We'll stop spouting spoilers now. Have fun exploring all the
    entries!

but that was changed to:

    ...We'll stop spouting deobfuscation information now. Have fun
    exploring all the entries!

which wasn't really about deobfuscation but just a brief summary of what
the entries did.

And in the most problematic case (at least for me :-), 2018/ferguson) I
had put a joke in:

    ... but it's the only Easter egg I won't spoil

but it was changed to 'won't deobfuscate' which not only is not what it
is but it spoilt the joke.

In some cases the word was changed back to 'SPOILER' (or similar) but in
most cases not. I believe it should be better now. There are some
caveats, however, as below.

Although make find_missing_links is okay I do not remember if this will
catch links that refer to '%%REPO_URL%%' or other pandoc tokens. This
means I might have to go back to some earlier years to verify links are
okay. That should not take that much time I hope.

It might also be that some wording can still be improved some but it is
hoped this will be discovered when checking links and looking over the
manifest (which obviously changed).

1994/horton/README.md

@@ -68,7 +68,7 @@ numbers to get a pleasing result, or use it for your high school algebra
 class.
 
 
-### DEOBFUSCATION:
+### SPOILER:
 
 As should be obvious from 20 feet away, the program is a cubic plotter.
 It plots against certain artists, splattering their cubes with graphs

1994/horton/index.html

@@ -429,7 +429,7 @@ newsletter and a PDF file of just the pages cited.</p>
 <p>Run it with any 4 numeric arguments, e.g. <code>./horton 3 2 1 0</code>. Play with the
 numbers to get a pleasing result, or use it for your high school algebra
 class.</p>
-<h3 id="deobfuscation">DEOBFUSCATION:</h3>
+<h3 id="spoiler">SPOILER:</h3>
 <p>As should be obvious from 20 feet away, the program is a cubic plotter.
 It plots against certain artists, splattering their cubes with graphs
 of their cubic equations. Those dastardly arguments are mere coefficients,

1994/imc/README.md

@@ -44,7 +44,7 @@ parameter or an invalid parameter is given, then 5 is assumed.  The
 maximum parameter is determined only by the amount of CPU time, virtual
 memory and display (or file) space available.
 
-### DEOBFUSCATION:
+### OBFUSCATION:
 
 OK, so you have probably seen magic square printers before.  But what
 about one that deals with even sizes as well as odd ones, or one that

1994/imc/index.html

@@ -424,7 +424,7 @@ other functions (apart from <code>main()</code>).</p>
 parameter or an invalid parameter is given, then 5 is assumed. The
 maximum parameter is determined only by the amount of CPU time, virtual
 memory and display (or file) space available.</p>
-<h3 id="deobfuscation">DEOBFUSCATION:</h3>
+<h3 id="obfuscation">OBFUSCATION:</h3>
 <p>OK, so you have probably seen magic square printers before. But what
 about one that deals with even sizes as well as odd ones, or one that
 prints out a different one each time (or attempts to, at any rate)?</p>

1994/schnitzi/README.md

@@ -85,8 +85,6 @@ compile it and compare how it works to the original code.
 
 ## Author's remarks:
 
-### DEOBFUSCATION:
-
 This is a program which takes any text file as input and 'flips'
 the input file along a diagonal running from the top left corner
 down to the bottom right.  In other words, the first row in the

1994/schnitzi/index.html

@@ -439,7 +439,6 @@ find out why?</p>
 <p>You might also wish to redirect the output to another file,
 compile it and compare how it works to the original code.</p>
 <h2 id="authors-remarks">Author’s remarks:</h2>
-<h3 id="deobfuscation">DEOBFUSCATION:</h3>
 <p>This is a program which takes any text file as input and ‘flips’
 the input file along a diagonal running from the top left corner
 down to the bottom right. In other words, the first row in the

1994/tvr/README.md

@@ -5,7 +5,7 @@
 ```
 
 
-The author provided a deobfuscated version as alternate code. See [Alternate
+The author provided a spoiler version as alternate code. See [Alternate
 code](#alternate-code) below.
 
 
@@ -39,7 +39,7 @@ Mode may be a value from 0 to 12.
 
 ## Alternate code:
 
-The author provided us a deobfuscated version that might be of interest to some.
+The author provided us a spoiler version that might be of interest to some.
 
 
 ### Alternate build:

1994/tvr/index.html

@@ -403,7 +403,7 @@ Location: <a href="../../location.html#FI">FI</a> - <em>Republic of Finland </em
 <!-- BEFORE: 1st line of markdown file: 1994/tvr/README.md -->
 <h2 id="to-build">To build:</h2>
 <pre><code>    make all</code></pre>
-<p>The author provided a deobfuscated version as alternate code. See <a href="#alternate-code">Alternate
+<p>The author provided a spoiler version as alternate code. See <a href="#alternate-code">Alternate
 code</a> below.</p>
 <h3 id="bugs-and-misfeatures">Bugs and (Mis)features:</h3>
 <p>The current status of this entry is:</p>
@@ -416,7 +416,7 @@ code</a> below.</p>
 <pre><code>    ./try.color.sh              # for colour displays
     ./try.bw.sh                 # for Black &amp; White displays</code></pre>
 <h2 id="alternate-code">Alternate code:</h2>
-<p>The author provided us a deobfuscated version that might be of interest to some.</p>
+<p>The author provided us a spoiler version that might be of interest to some.</p>
 <h3 id="alternate-build">Alternate build:</h3>
 <pre><code>    make alt</code></pre>
 <h3 id="alternate-use">Alternate use:</h3>

1994/westley/README.md

@@ -111,13 +111,7 @@ To see the game from start to complete, try:
 
 Not all compiler errors are bad.
 
-For deobfuscation information see the end of the notes from the author below.
-
-To use:
-
-``` <!---sh-->
-    ./try.sh
-```
+For spoilers see the end of the notes from the author below.
 
 
 ## Author's remarks:
@@ -174,7 +168,7 @@ The goal of the game is to escape the dungeon.
 Here is a walk-through for the game, including a few dead-ends:
 
 
-### DEOBFUSCATION
+### SPOILER (HOW TO WIN):
 
 ``` <!---sh-->
     cc -Describe -Door westley.c

1994/westley/index.html

@@ -463,9 +463,7 @@ arguments:</p>
 <pre><code>    ./try.sh</code></pre>
 <h2 id="judges-remarks">Judges’ remarks:</h2>
 <p>Not all compiler errors are bad.</p>
-<p>For deobfuscation information see the end of the notes from the author below.</p>
-<p>To use:</p>
-<pre><code>    ./try.sh</code></pre>
+<p>For spoilers see the end of the notes from the author below.</p>
 <h2 id="authors-remarks">Author’s remarks:</h2>
 <p>This program, in accordance with the rules, compiles into a legal
 C program without human intervention. However, it simply compiles
@@ -501,7 +499,7 @@ the opening message each time, as if you are playing an adventure game
 with “verbose” turned on).</p>
 <p>The goal of the game is to escape the dungeon.</p>
 <p>Here is a walk-through for the game, including a few dead-ends:</p>
-<h3 id="deobfuscation">DEOBFUSCATION</h3>
+<h3 id="spoiler-how-to-win">SPOILER (HOW TO WIN):</h3>
 <pre><code>    cc -Describe -Door westley.c
     cc -Describe -Drain westley.c
     cc -Describe -Dwarf westley.c