local: Use new config system
stream: Use new config system
lastfm: Use new config system
mpris: Use new config system
http: Use new config system
mpd: Use new config system
Merge branch 'develop' into feature/use-new-config

Conflicts:
	mopidy/frontends/scrobbler/actor.py
mpd: Fix two test failures
audio: Use new config system
main: Use new config system
settings: Remove SettingsProxy at mopidy.settings
settings: Remove settings module
settings: Remove settings utils
scanner: Use new config
Merge branch 'develop' into feature/use-new-config
scrobbler: Update to use 'scrobbler' config values
http: Revert to use 'static_dir'
Merge pull request #395 from jodal/feature/use-new-config

Update all frontends and backends to use new config system