Move css and css-value modules to the toplevel.

This is the default location when installing from npm, and Angular uses
that when parsing CSS.

Updated module paths, requires, csproj, tsconfig and grunt tasks.

ui/styling/style-scope.ts

@@ -1,7 +1,7 @@
 import view = require("ui/core/view");
 import trace = require("trace");
 import cssSelector = require("ui/styling/css-selector");
-import cssParser = require("js-libs/reworkcss");
+import cssParser = require("css");
 import {VisualState} from "ui/styling/visual-state";
 import application = require("application");
 import utils = require("utils/utils");