Fix #78: MPRIS OpenUri() does not start playing

Fix issue #78: <https://github.com/01org/dleyna-renderer/issues/78>

Update the code to not call Play.

Signed-off-by: Ludovic Ferrandis <ludovic.ferrandis@intel.com>
MediaRenderer openURI / prefetchURI APIs use DOM promises
Merge branch 'master' into mobile-dmc

Conflicts:
	js/main.js