Removed unnecessary Control Object() use
added connectValueChanged to ControlObjectThread
Introduced ControlObjectSlave a successor of ControlObjectThread.
ControlObjectSlave connects only on demand and has no "From this
signal". Because connect is a static Qt funtion it might be to risky to
remove ControlObjectThread yet. ControlObjectSlave should be used in new
code.
Added default constructor, Connect to ControlObjectPrivate only if
required.
changed EnigineBuffer::m_pSampleRate to ControObjectSlave
changed addition COs to COSs in ClockControl and BpmControl
Merge branch 'master' into atomic-co
added some usage comments to controlobjectslave.h
Merge branch 'master' into atomic-co

Conflicts:
	src/engine/enginecontrol.cpp
Merge pull request #38 from daschuer/atomic-co

Introduced ControlObjectSlave and converted fist slave Cos to this