Merge the media edit and media insert dialogs. Allow editing
of media properties when inserting a new image, and also
allow the user to replace the image on edit.
Bug: 67170
Change-Id: I35bd95503565dbf95090ee8110284db5a8fbba83
Reorganize stylesheets in VE-MW to match JS directory structures,
and update VisualEditor.php for similar reorganization in VE core.
New changes:
c6ed962 Reorganize stylesheets
Change-Id: I4f1070643744fb2ee6726cb03e012e31a9a05c64