[conf] altura calibrated + gps
[conf] default flash mode
[gps] refactor sending of SVINFO

- when using only GPS or GPS_INT messages:
  send SVINFO for all satellites while no GPS fix,
  after 3D fix, send avialable sats only when there is new information
- possibility to add SVINFO to periodic telemetry, sends it for all sats
[rotorcraft] fix USE_KILL_SWITCH_FOR_MOTOR_ARMING
[conf] asctec_cdw bugfix
Merge pull request #1038 from paparazzi/fix_kill_switch_arming

[rotorcraft] fix USE_KILL_SWITCH_FOR_MOTOR_ARMING
second release candidate for next stable release v5.4
[rotorcraft] switching to MODE_MANUAL allowed even during HOME_MODE
[rotorcraft] error if MODE_MANUAL == AP_MODE_NAV
[conf] switched to yaw arming due to remaining problems
[unit] 1m = 3.2ft
[messages] rename measure fields in VFF_EXTENDED
[conf][telemetry] ardrone: VFF_EXTENDED in vert_loop
[boards] ardrone baro: send temperature via ABI
[blackmagic] crc break uploading to blackmagic. own stm_mem fixes.
[nav_airspeed] tune navigation airspeeds for diffent phases of the flightplan
[nav_airspeed] Descriptions
[dox] stylec: limit to 100 chars
[conf] remove NPS_JSBSIM_INIT from all example airframes

most people want it to start at flightplan location anyway...
If someone wants to explicitly set the initial conditions, they can add whatever xml file they want...
Merge pull request #1036 from paparazzi/mode_manual_allowed_even_during_home

always allow switching to MODE_MANUAL via RC (even during HOME or FAILSAFE)