Move `trailing` check to JSCS.

grunt/.jshintrc

@@ -7,6 +7,5 @@
   "node"     : true,
   "nonbsp"   : true,
   "strict"   : true,
-  "trailing" : true,
   "undef"    : true
 }

js/.jscsrc

@@ -7,6 +7,7 @@
   "disallowRightStickedOperators": ["?", "/", "*", ":", "=", "==", "===", "!=", "!==", ">", ">=", "<", "<="],
   "disallowSpaceAfterPrefixUnaryOperators": ["++", "--", "+", "-", "~"],
   "disallowSpaceBeforePostfixUnaryOperators": ["++", "--"],
+  "disallowTrailingWhitespace": true,
   "requireCamelCaseOrUpperCaseIdentifiers": true,
   "requireLeftStickedOperators": [","],
   "requireLineFeedAtFileEnd": true,