mavlink: in HIL_CONTROLS send 0 for disabled channels
mavlink: stream names updated in configuration
Merge pull request #1272 from PX4/mavlink_fixes

Mavlink fixes
Fixed copy & paste error on RC output
Merge pull request #1273 from PX4/rc_fix

Fixed copy & paste error on RC output
Merge remote-tracking branch 'upstream/master' into offboard2_externalsetpointmessages