runaway .RPP size when using "SWS/BR: Toggle hide all CC lanes" actions

Hi.  In BR_ProjState.cpp, m_ccLanes needs to be cleared in BR_MidiToggleCCLane::LoadState().  As it is now, the loaded state is always appended to the existing state, leading to runaway .RPP files as per this bug report:

http://forums.cockos.com/showthread.php?t=187449

Thanks!