So this special casing is no longer needed

Plus a large number of other changes to allow for orderly shutdown of
objects without crashes or asserts. This is need for unit tests to
create/delete global state around every test.

This is the Pixhawk research board, not the PX4 production board.

Conflicts:
	src/uas/QGCMAVLinkUASFactory.cc
	src/uas/QGCMAVLinkUASFactory.h

SLUGS has maintained their patches out-of-tree for a long while now.
These will eventually get merged back in, but it'll be easier to evaluate them as fresh commits instead of modifications to this old & dead code, so we'll delete this for now.

Fix HIL link reconnect issues due to missing threading flag usage, warn user about missing config and take him to config view if necessary

Fix HIL link reconnect issues due to missing threading flag usage, warn user about missing config and take him to config view if necessary

Enabled visualization of point cloud data via Protocol Buffers serialization and extended_mavlink_message.