commander: ignore battery voltage in HIL mode
commander: allow arming with safety enabled in HIL mode
tests: added "tests file2" filesystem test

this is useful for testing for filesystem corruption on cluster
boundaries
FMUv2: switch debug console and 2nd GPS

this allows a normal GPS cable to be used for the 2nd GPS, making
dual-GPS setups easier
Fixed warning
Merge branch 'master' of github.com:PX4/Firmware
Revert "Fixed warning"

This reverts commit 3639c7ae91f5226b71cdba8d8cc98eae4bba7e07.
mc_att_control: hotfix, memset all structs to zeroes on start, fixes garbage in actuator controls 4..8
Merge branch 'master' of github.com:PX4/Firmware into beta_mavlink