Add JSCS config file

Don't merge yet - feedback wanted.

JSHint people want to focus on syntax linting and are dropping style oriented
options. They recommends using JSCS (in addition to JSHint) for style:
jshint/jshint#1339

JSCS has recently added the options dropped from JSHint.
jscs-dev/node-jscs#102

This commit contains a JSCS config file with some basic settings that generate
very few errors with the existing cordova-cli and lib code.

Would be glad to get some feedback about this. My goal is to eventually run
JSCS together with JSHint as part of `npm test`. The nice thing about JSCS
is that style flame wars can be way more structured with it as we can argue
about very specific well named JSCS config options :)

I'm using it with SublimeLinter-jscs
https://sublime.wbond.net/packages/SublimeLinter-jscs

cordova-lib/.jscs.json

@@ -0,0 +1,22 @@
+{
+    "disallowMixedSpacesAndTabs": true,
+    "disallowTrailingWhitespace": true,
+    "validateLineBreaks": "LF",
+    "validateIndentation": 4,
+    "requireLineFeedAtFileEnd": true,
+    "requireCapitalizedConstructors": true,
+    "disallowSpaceAfterPrefixUnaryOperators": true,
+    "disallowSpaceBeforePostfixUnaryOperators": true,
+    "requireSpaceAfterLineComment": true,
+    "disallowSpacesInNamedFunctionExpression": {
+        "beforeOpeningRoundBrace": true
+    },
+
+    "requireSpaceAfterKeywords": [
+      "if",
+      "else",
+      "for",
+      "while",
+      "do"
+    ]
+}