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.

1992/gson/README.md

@@ -236,12 +236,10 @@ those bits that should remain zero.  For example, the following
 program prints all those 16-bit integers that contain zeroes in all
 even bit positions:
 
-
 ```c
 main(){int i=0,s=0xAAAA;do{printf("%04x\t",i);}while(i=((i|~s)+1)&s);}
 ```
 
-
 AG uses a similar method but works in the opposite direction, finding
 the next lower value with zeroes in given bit positions by propagating
 borrows across those bits.  Some additional adjustments are made