Fix missing space after , errors

Author: rjmunro

scripts/cpplint.py

@@ -553,6 +553,7 @@
   "Tab found, replace by spaces": r's/\t/  /',
   "Line ends in whitespace.  Consider deleting these extra spaces.": r's/\s*$//',
   "You don't need a ; after a }": r's/};/}/',
+  "Missing space after ,": r's/,\([^ ]\)/, \1/',
   # "Statement after an if should be on a new line": r's/^\(\s*\)if *\(([^()]*)\) *\(.*\)$/\1if\2\n\1  \3/', # Single layer of nested bracets
   # "Statement after an if should be on a new line": r's/^\(\s*\)if *\((\([^()]\|([^()]*)\)*)\) *\(.*\)$/\1if\2\n\1  \4/', # Max 2 layers of nested bracets; messes up line numbers for other errors.
   # "Redundant blank line at the end of a code block should be deleted.": "d", # messes up line numbers for other errors.