store pointer to creating CO in CDP
Removed separate Hash table from ControlObject.
Merge branch 'master' into atomic-co2
Introduce QSharedPointer for ControlDoublePrivate
Fix double add to hashtable
Delete all leaking cdp one shutdown
Changed some ControlObjectThreadMain instances to ControlObjectThread if
no direct connection is used.
Changed some more ControlObjectThreadMain instances to
ControlObjectThread if no direct connection is used.
Finaly Changed remaining ControlObjectThreadMain instances to
ControlObjectThread where no direct connection is used.
Merge branch 'master' into atomic-co2

Conflicts:
	src/control/control.cpp
	src/control/control.h
Merge branch 'master' into atomic-co3
call select() by changed signalfrom PlaylistDAO to have PlaylistTableModel always up to date. Fixes https://bugs.launchpad.net/mixxx/+bug/1213603
Fixed drag and drop position and removed duplicated code, fixes https://bugs.launchpad.net/mixxx/+bug/1213734
Moved parts of PlaylistTableModel::moveTrack to playlistdao, inform Models when tracks are hiden from library. Made some funtions const.
move db queries for schuffleTracks to PlaylistDAO
split long queries in removeTracksFromPlaylists
AutoDJ shuffle respects selected tracks, fixes https://bugs.launchpad.net/mixxx/+bug/1169438
added missing trackIdList.clear()
fixes from  kain88-de comments
The preview column should not be part of the exported csv file