Redesign qtSelectionManger with one output signal and shared_ptr
This MR redesigns the qtSelectionManager
so that we use one universal
signal to broadcast to all receivers(rendering window, model tree and
attribute panel). Also now qtActiveObjects has a weak reference to
qtSelectionManager.
qtSelectionManger
now uses "{className}_
{memoryAddress}" to avoid
updating the senders again.
Clear a bunch of selection legacy codes and simplify the logic.
close #137 (closed)