Some minor changes to c and xml

c.nanorc

@@ -29,7 +29,7 @@ color magenta "[(){}]" "\[" "\]"
 color cyan "<[^= 	]*>" ""(\\.|[^"])*""
 ##
 ## This string is VERY resource intensive!
-color cyan start=""(\\.|[^"])*\\[[:space:]]*$" end="^(\\.|[^"])*""
+#color cyan start=""(\\.|[^"])*\\[[:space:]]*$" end="^(\\.|[^"])*""
 
 ## Comment highlighting
 color brightblue "//.*"

xml.nanorc

@@ -1,7 +1,7 @@
 ## Here is an example for xml files.
 ##
 
-syntax "ml" ".*\.([jrs]?html?|xml|sgml?)$"
+syntax "ml" ".*\.([jrs]?html?|xml|sgml?|rng)$"
 color white "^.+$"
 color green  start="<" end=">"
 color cyan   "<[^> ]+"