REMOVE ME temp enable failing tests: libassuan/fdpassing  libgcrypt/random
handle OI File Manager's odd content:// URI for file paths

OI File Manager SHAREs files using the full path to the file, but uses a
URI scheme of content:// and a URI host of org.openintents.filemanager.
This detects that and strips it down to a proper file:// URI so its handled
like a plain file path.

refs #1646