Add (partial) support for assets catalog

Add supports for assets catalog to ninja generator (make generator does
not support them but avoid copying the catalog into the bundle).

Only supports generating compressed catalog, so will only work if target
is Mac OS X >= 10.9 or iOS >= 7.0. Support for application icon and for
launch image is partially implemented in that there is no way to enable
it.

BUG=gyp:458

git-svn-id: http://gyp.googlecode.com/svn/trunk@1991 78cadc50-ecff-11dd-a971-7dbc132099af