cleanup winner README.md files

Fixed cases where there was a bad trailing backslash.

Improved a few cases where a code block was needed
to highlight some text.

Changed a few cases where a code block needed to
declared as, say, a sh code block.

Fixed a few cases where the winner information was not properly formatted.

Plus a few nits and clarifying text was added.

1988/isaak/README.md

@@ -28,7 +28,7 @@ The original version of this code is in [isaak.alt.c](isaak.alt.c).
 The original entry starts with the line:
 
 ```c
-	main(){};
+main(){};
 ```
 
 This works on some systems.  Why?  Note that `#include <stdio.h>` is given on