Support for Windows Transparency

* Added DWM functionality
* Added background clearing
* New switch to package.json
* New Window.isTransparent getter to signal if transparency is enabled
* New window.beginMouseOffclient to trap mouse events offscreen (needed for resizing transparency)
* New Window.endMouseOffclient to end trapping mouse events offscreen (needed for resizing transparency)
Transparency support in Mac OS X
Fixed bug where composition isn't established correctly.
Added webgl support in preferences.
Merge branch 'transparency' of https://github.com/trevorlinton/node-webkit into transparency
Merge branch 'master' into transparency

Conflicts:
	src/api/window/window.cc
	src/browser/native_window.cc
	src/browser/native_window_win.cc
Added myself to Authors
Support Snow Leopard Transparency
Merge branch 'transparency'

Conflicts:
	AUTHORS
Initial embed protocol
A new method for extracting content. This defines a new protocol handler called embed://
The handler will look within <local>/Content/Resource/Package on MacOSX or the executable
on windows for a magic key and filename (requested by embed://). If matched it will return
a gzipped location of the stream on the executable for chromium's net protocol handler to
consume.  See the source code in net/util/embed_utils.cc for format.
Extraction
 Changes to runtime and embed