Add a more friendly Browser permutation for Camera plugin

Related issue - https://code.google.com/p/gwt-phonegap/issues/detail?id=19

Uses a hidden file input to load an image from the file system.
Picture options can be set to user data uri or file uri.
The default rebind rule for the desktop is still CameraBrowserImpl

Browser Support:
* IE 10+
* Firefox 29+
* Chrome 31+
* Safari 7+
* Opera 22+

Caveats:
It's only possible to have a picture if the API is called in mouse event handling context
Merge pull request #39 from yarcub/camera-browser

Add a more friendly Browser permutation for Camera plugin