Update for app framework removal

Changes:
- Remove the autobuild scripts and config.xml used by the app
  framework widget build.
- Update the CMake files to just build a "camera-gstreamer" binary
  and install it into /usr/bin by default.
- Remove the code in main.cpp that handled reading the WebSocket
  command-line arguments and passing them to binding related
  code.
- Added installation of a minimal .desktop file to work with the
  new applaunchd.

Bug-AGL: SPEC-4284

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I87816800c117a243a107eecb8895f07d6c90f23a