replace trailing whitespace with blackslash in README.md

As an alternative to the markdown trailing whitespace as a line
break, we use a trailing blackslash as a markdown line break.

1996/rcm/README.md

@@ -1,8 +1,8 @@
 # Best RFC Obfuscation
 
-Ron McFarland  
-7941 Fawncreek Drive  
-Cincinnati, Ohio 45249  
+Ron McFarland\
+7941 Fawncreek Drive\
+Cincinnati, Ohio 45249\
 US
 
 ## To build: