Improve markdown guidelines wording

Amongst the changes here is that we do not need to have the hex or html
code (numbers) for open and close parentheses (in links) as there are
names. '(' is & followed by lpar; and the ')' is the same but 'rpar;'
instead. This makes it easier to remember and type and it generates the
same html as well (they are all valid). Now the markdown files are
consistent in this (in some cases hex was used and in others the html
code).

Although many markdown files were updated no html files needed to be
updated as it generates the same html. Even so I ran the appropriate
rules to do so just to verify this.

1986/README.md

@@ -13,7 +13,7 @@ A poll was taken for the worst code for
 [BSD](https://en.wikipedia.org/wiki/Berkeley_Software_Distribution) and [System
 V](https://en.wikipedia.org/wiki/UNIX_System_V) program.  The [Bourne
 Shell](https://en.wikipedia.org/wiki/Bourne_shell) (`/bin/sh`) won for both
-systems.  The BSD [finger](https://en.wikipedia.org/wiki/Finger_(protocol))
+systems.  The BSD [finger](https://en.wikipedia.org/wiki/Finger_(protocol))
 program took third place.
 
 [Rules](rules.txt) and [results](../years.html#1986) were posted to _net.lang.c_

1986/wall/README.md

@@ -40,8 +40,8 @@ This caused a number of System V C pre-preprocessors to gripe about a
 syntax error.
 
 This program is a masterpiece of obfuscation and humor.  Larry Wall (the hacker
-who gave us [rn](https://en.wikipedia.org/wiki/Rn_(newsreader)) and
-[patch](https://en.wikipedia.org/wiki/Patch_(Unix)), etc.) asks you to compile and
+who gave us [rn](https://en.wikipedia.org/wiki/Rn_(newsreader)) and
+[patch](https://en.wikipedia.org/wiki/Patch_(Unix)), etc.) asks you to compile and
 consider the warning message generated by the C compiler.  Then execute the
 program and type characters into its standard input.  You will see why the
 compiler documents the program.