Change 'tri-graphs' to 'trigraphs' - it's one word

The is a file excluded from this commit that has had the change because
there are other changes but the file is incomplete. That file will be
committed when the fixes are complete which will happen at a later date.

2000/guidelines.txt

@@ -43,7 +43,7 @@ HINTS AND SUGGESTIONS:
     a number of tests to an entry:
 
 	* look at the original source
-	* convert ANSI tri-graphs to ASCII
+	* convert ANSI trigraphs to ASCII
 	* C pre-process the source ignoring '#include' lines
 	* C pre-process the source ignoring '#define' and '#include' lines
 	* run it through a C beautifier
@@ -177,7 +177,7 @@ OUR LIKES AND DISLIKES:
 	* depend on a utility or application not normally found on most
 	  most POSIX P1003.1/P1003.2 like systems
 	* abuse the build file to get around the size limit
-	* obfuscate by excessive use of ANSI tri-graphs
+	* obfuscate by excessive use of ANSI trigraphs
 	* are longer than they need to be
 	* are similar to previous winners
 	* are identical to previous losers  :-)

2000/rince/README.md

@@ -236,7 +236,7 @@ common tricks. Taken through the standard rounds listed in the
     space saved by using a single long string constant is more than
     outweighed by the ability to further obfuscate.
 
-2. convert ANSI tri-graphs to ASCII
+2. convert ANSI trigraphs to ASCII
 
     These are not used.