Updated backside controller/ added backside config.
Added local position pub to att_pos_esitmator_ekf
Added local position publication to mavlink receiver for HIL.
Improved mode mapping for fixedwing_backside.
Fixed backside automode typo.
Merge pull request #530 from jgoppert/backside

Backside update/ python HIL fix
Merge remote-tracking branch 'upstream/master'