Rename syntax definitions

Duplicate syntax definition names may cause problems.
Since nano comes with predefined all-lowercase syntax definitions,
we use uppercase letters everywhere to reduce the risk of future conflicts

awk.nanorc

@@ -1,4 +1,4 @@
-syntax "awk" "\.awk$"
+syntax "AWK" "\.awk$"
 header "^#!.*bin/(env +)?awk( |$)"
 
 color brightyellow "\$[A-Za-z0-9_!@#$*?-]+"