add hack-a-round for language specified markdown code blocks

When language is specified in a markdown code block such as:

````
```c
    printf("Hello, world!\n");
```
````

is used, the resulting HTML as produced by `pandoc(1)` combined
with our revised `ioccc.css` is not intent the code block well.

A temporary "_hack-a-round_" is to turn the "markdown code language
specifier" into an HTML comment.  For example:

````
```<!---c-->
    printf("Hello, world!\n");
```
````

This commits turns off existing markdown code language specifiers
for now, while preserving our ability to restore them in the future
when a better  "_hack-a-round_" to the "markdown code language
specifier" problem is found.

The HTML impact if this "_hack-a-round_" is to produce HTML that
looks like this:

```
<pre class="&lt;!---c--&gt;"><code> .. </code></pre>
```

We might be able to create a complex set of classes for each markdown
code language (there won't be very many) in `ioccc.css`, or we might
find a more general CSS (or maybe `pandoc(1)`?) solution.

For now, this hack-a-round will have to do.

2012/konno/README.md

@@ -1,6 +1,6 @@
 ## To build:
 
-```sh
+```<!---sh-->
     make
 ```
 
@@ -10,14 +10,14 @@ code](#alternate-code) below.
 
 ## To use:
 
-```sh
+```<!---sh-->
     ./konno N
 ```
 
 
 ## Try:
 
-```sh
+```<!---sh-->
     ./try.sh
 
     # you can also specify numbers to try before the random and preselected ones:
@@ -36,7 +36,7 @@ This alternate code is an unobfuscated version of the winning code.
 
 ### Alternate build:
 
-```sh
+```<!---sh-->
     make alt
 ```
 
@@ -64,7 +64,7 @@ patterns.
 
 Try:
 
-```sh
+```<!---sh-->
     ./konno 30
     ./konno 90
     ./konno 102
@@ -79,13 +79,13 @@ There are 256 (from 0 through 255) possible rules.
 
 This program uses bit operations. I think
 
-```c
+```<!---c-->
     7&O<<!o>>!o+29
 ```
 
 is an interesting operation. This isn't equal to
 
-```c
+```<!---c-->
     7&O>>29
 ```