fw landing: improve slope altitude calc to avoid climbout after waypoint. Throttle cut is now defined via altitude
startup: make sdlog2 working again on FMUv1
position_estimator_inav: lower RAM
Fix for hexa mixer
Revert "position_estimator_inav: lower RAM"

This reverts commit b457e714972649f5a39fa3f2f9463bdfe6971fcc.
Merge pull request #633 from PX4/fmuv1_ram_cleanup

Fmuv1 ram cleanup
Startup: Hex vs Hexa
Merge pull request #639 from PX4/fix_hex_startup

Startup: Hex vs Hexa
Startup: Raise min throttle
Merge pull request #640 from julianoes/mc_min_throttle

Startup: Raise min throttle
Mixer load: don't upload empty mixers from non-existing files
Merge pull request #641 from julianoes/fix_mixer_load

Mixer load: don't upload empty mixers from non-existing files
Merge pull request #629 from thomasgubler/beta_avoidclimbout

fw landing: improve slope altitude calc to avoid climbout after waypoint, throttle cut is now defined via altitude
FMUv2: fixed UART3 flow control pins
Merge branch 'beta' of github.com:PX4/Firmware into beta
Merge remote-tracking branch 'px4/beta' into acro2