syntax: tcl: colorize comments normally, not with a background hue

This makes for a less "messy" and more readable appearance.

Suggested-by: Michael Siegel <msi@malbolge.net>

syntax/tcl.nanorc

@@ -17,4 +17,5 @@ color green "(\(|\)|\;|`|\\|\$|<|>|!|=|&|\|)"
 color brightyellow ""(\\.|[^"])*"" "'(\\.|[^'])*'"
 icolor brightred "\$\{?[0-9A-Z_!@#$*?-]+\}?"
 color ,green "[[:space:]]+$"
-color ,magenta "^[[:space:]]*#.*"
+# Comments:
+color cyan "^[[:space:]]*#.*"