roomservice: Fix os.path.isdir calls

Apparently on some Python installations
it throws exception instead of returning False.

Change-Id: I9d901e3260bab411cf3466346c421594f0922562
roomservice: Add -f and --no-clone-bundle flags to repo sync

Suppress scary-looking common warnings during resolving.

Change-Id: I4337ec95992ad68ff4471b0d0b7346e933269503