Keep modules in separate dirs, move images to their module dirs, and fix
up the module declarations so they still work.
Also moved viewer.svg into the root.
Bug: 56421
Change-Id: Ia84ddfd3b91c784c42d9ba243c5cfd46354f139f
Strips out complex formatting, which should be useful later on as well.
Depends on:
* core
:* I77303d8e535fc1c42e14cfb853814e5c434a81ec
* CommonsMetadata
:* I5e6bc45f9751641e16426231dabcc8277b86fee0
Change-Id: Id835fd8133b9762e7bec10783f4fa4b983177aed