Small import fix
Merge pull request #335 from Tribler/import_fix

Small import fix
Use latest Dispersy devel.
Start Dispersy message.

Also fixes a bug where the DIFF variable was not set if dispersy.stop()
returned False.
Merge remote-tracking branch 'upstream/devel' into downloadconfig

Conflicts:
	Tribler/Core/APIImplementation/LaunchManyCore.py