[QML PFD]: Fixes an issue by which the PFD was continuing to process
events even when it was no longer visible. This specifically sets the
processed states to 0 as long as the PFD is not visible, and sets them to
the corresponding UAVO when they are.

On OSX with Qt 4.8, this saved 14% processor load.
Merge pull request #918 from kubark42/fix-qml-cpu-usage

Fixes an issue by which the PFD was continuing to process events even when it was no longer visible.
Split ManualControlCommand and ManualControlSettings UAVOs into
ControlCommand, ControlCommandSettings, RCTransmitterInput, and
RCTransmitterSettings.
Upgraded targets to support new ControlCommand UAVOs.
Added support for new UAVOs to GCS. There is no new
functionality, although in configinputwidget.h some of the new
UAVO data structs were not declared class memebers.
Changed the XML formatting to make it easier to add new control
channels.
Fixed rebase compile bug.