Change alt/orig to build/to use heading levels

As the 'Alternate code' and 'Original code' heading level is now 2 the
'To build' and 'To use' subsections should be level 3, not 4, and also
reworded, this was done:

    sgit -e 's/^#### To build/### Alternate build/g' -e 's/^#### To use/### Alternate use/g' '*README.md'

Many more have to be updated and this will be done manually at another
time.

1984/anonymous/README.md

@@ -21,13 +21,13 @@ in order to show the code that was turned into the
 [tattoo](https://web.archive.org/web/20070120220721/https://thomasscovell.com/tattoo.php),
 as the alternate code. See below in the tattoo side-by-side with the code.
 
-#### To build:
+### Alternate build:
 
 ```sh
 make alt
 ```
 
-#### To use:
+### Alternate use:
 
 NOTE: this version might not work on some systems like macOS.
 

1984/decot/README.md

@@ -20,13 +20,13 @@ This alternate code, the original, requires a compiler that supports
 `-traditional-cpp` or an old enough compiler. If you have such a compiler you
 can use this entry.
 
-#### To build:
+### Alternate build:
 
 ```sh
 make alt
 ```
 
-#### To use:
+### Alternate use:
 
 ```sh
 ./decot.alt

1984/mullender/README.md

@@ -34,7 +34,7 @@ as it goes so fast in modern systems. The author suggested that there was a
 delay in the original code as well.
 
 
-#### To build:
+### Alternate build:
 
 
 ```sh
@@ -42,7 +42,7 @@ make alt
 ```
 
 
-#### To use:
+### Alternate use:
 
 ```sh
 ./mullender.alt [microseconds]
@@ -122,7 +122,7 @@ close to as the original as possible we used a copy of
 in the *fabulous* [Unix History
 Repo](https://github.com/dspinellis/unix-history-repo/tree/Research-Release).
 
-#### To build:
+### Alternate build:
 
 `gentab.c` can be built like:
 
@@ -131,7 +131,7 @@ Repo](https://github.com/dspinellis/unix-history-repo/tree/Research-Release).
 make gentab
 ```
 
-#### To use:
+### Alternate use:
 
 ```sh
 ./gentab file

1985/lycklama/README.md

@@ -63,13 +63,13 @@ appreciate what it does, we encourage you to first try the alternate version.
 After this, however, you might wish to try the original version, fixed for
 modern systems.
 
-#### To build:
+### Alternate build:
 
 ```sh
 make all
 ```
 
-#### To use:
+### Alternate use:
 
 
 ```sh

1985/sicherman/README.md

@@ -32,14 +32,14 @@ This alternate version, which is the original entry, requires either an old
 enough compiler or a compiler that supports `-traditional-cpp`. If you have such
 a compiler you can try this version.
 
-#### To build:
+### Alternate build:
 
 
 ```sh
 make alt
 ```
 
-#### To use:
+### Alternate use:
 
 ```sh
 ./sicherman.alt < file

1986/marshall/README.md

@@ -98,7 +98,7 @@ If the optimiser is enabled, however, we will see that it works fine before the
 change to `_exit()`.
 
 
-#### To use:
+### Alternate use:
 
 Due to the different conflicting problems with gcc and clang, we instead offer
 the problematic code as an alternate version whereas [marshall.c](marshall.c)

1986/wall/README.md

@@ -20,7 +20,7 @@ make all
 If you have an old compiler or a compiler that supports `-traditional-cpp` you
 might enjoy looking at the original source in [wall.alt.c](wall.alt.c).
 
-#### To build:
+### Alternate build:
 
 ```sh
 # if you have an old enough compiler:

1988/applin/README.md

@@ -26,7 +26,7 @@ program.  See the [Alternate code](#alternate-code) section below for details.
 As noted above a smaller version can be used in case your `cpp` has a hard time
 with this entry.
 
-#### To build:
+### Alternate build:
 
 ```sh
 make alt

1988/isaak/README.md

@@ -37,7 +37,7 @@ using that macro for `#define`.
 This version will not likely work on modern systems if you can even get it to
 compile.
 
-#### To build:
+### Alternate build:
 
 ```sh
 make alt

1988/litmaath/README.md

@@ -31,7 +31,7 @@ This alternate code, added to help understand the entry and for fun, is code
 that we suggested at the time of the entry publication but which we never put in
 a file.
 
-#### To build:
+### Alternate build:
 
 
 ```sh

1989/jar.1/README.md

@@ -30,7 +30,7 @@ make clobber all
 
 This code, which prints something slightly different, is provided as well.
 
-#### To build:
+### Alternate build:
 
 NOTE: this will run the program itself.
 
@@ -38,7 +38,7 @@ NOTE: this will run the program itself.
 make clobber alt
 ```
 
-#### To use:
+### Alternate use:
 
 Alternatively, you can run it directly:
 

1989/paul/README.md

@@ -28,13 +28,13 @@ the program.  Besides it is fun to watch the tape zooming back
 and forth as the program runs.  A much better debugger or trace
 could easily be added.
 
-#### To build:
+### Alternate build:
 
 ```sh
 make alt
 ```
 
-#### To use:
+### Alternate use:
 
 ```sh
 ./paul.alt

1989/tromp/README.md

@@ -53,7 +53,7 @@ loser](https://web.archive.org/web/20181023221954/https://www.chicagotribune.com
 The author provided an alternate version of the code with some improvements. See
 the judges' additional remarks in the author's remarks, for more details.
 
-#### To use:
+### Alternate use:
 
 ```sh
 make alt

1990/baruch/README.md

@@ -40,13 +40,13 @@ Turbo-C or MSC, the code is based on the authors' remarks except that the `"
 improved output though admittedly we have no way to test the compilers in
 question. YMMV.
 
-#### To build:
+### Alternate build:
 
 ```sh
 make alt
 ```
 
-#### To use:
+### Alternate use:
 
 Use `baruch.alt` as you would `baruch`.
 

1995/garry/README.md

@@ -35,14 +35,14 @@ judges noted that the C pre-processed version (with the `#include`s
 left intact) looked very much like a rat "dropping core".  See
 [garry.alt.c](garry.alt.c) and judge for yourself!
 
-#### To build:
+### Alternate build:
 
 
 ```sh
 make alt
 ```
 
-#### To use:
+### Alternate use:
 
 ```sh
 ./garry.alt <input_file >output_file

2012/kang/README.md

@@ -44,13 +44,13 @@ Germans that causes other problems for Germans so if you're German you'll just
 have to deal with it :-) It is, however, good as you can appreciate the entry
 even more.
 
-#### To build:
+### Alternate build:
 
 ```sh
 make alt
 ```
 
-#### To use:
+### Alternate use:
 
 ```sh
 echo vier | ./kang.alt