Fixed bug when trying to use gc -m "commit message"

lib/git/status_shortcuts.sh

@@ -107,6 +107,8 @@ git_expand_args() {
         files="$files $(eval echo \$$git_env_char$i)"
       done
     else   # Otherwise, treat $arg as a normal string.
+      # If arg contains any spaces, (re)wrap it in double quotes
+      if echo $arg | grep -q " "; then arg="\"$arg\""; fi
       files="$files $arg"
     fi
   done