Trajectory - Add time synchronization between trajectories. Split update(...) function into updateDurations(...) and integrate(...) to be able to insert time synchronization in between.

Derivation by Mathieu Bresciani:
https://github.com/Auterion/trajectory_generator

* Add attitude sub to mc_pos_control for yaw usage.

* Initialize pos control _states struct.

* Remove unnecessary init for struct in mc pos ctrl.

* Only use att topic for yaw setting in FlightTask.

Signed-off-by: Roman <bapstroman@gmail.com>

Signed-off-by: Roman <bapstroman@gmail.com>

 - only SENSOR_POLLRATE_DEFAULT is needed

 - only used in self tests

Fixes these invalid format strings:
- A `%d` for a pointer (replaced it by `%p`)
- A 0x%08x (and a 0x%0x8!) for a pointer (replaced by %p)
- 2 cases of `%d` for a `ssize_t` (replaced it by `%zi`)
- 1 case of a %u for an `int` (replaced by %i)
- 3 cases of %d for a `long` (replaced by %ld)
- 19 cases of `%d`, `%i`, `%u` or `%lu` for a `size_t` (replaced it by `%zu`)
- An unused formatting argument (removed it)
- A missing `%d` (added it)
- A missing `%s` (added it)
- 2 cases of `%llu` for a `uint64_t` (replaced it by `"%" PRIu64`)
- 6 cases of giving a string directly as format string (replaced it by `("%s", string)`)
- 2 cases of %*-s, which should probably have been %-*s.
  (Looks like NuttX accepts (the invalid) %*-s, but other platforms don't.)
- A %04x for a `uint32_t` (replaced by "%04" PRIx32)

If the filter was disabled, the apply() would always return 0.

    - ecl in PX4/Firmware (bd71d1cd9e1e1d29f89351c43f879e6c49b727bc): https://github.com/PX4/ecl/commit/f240eaa5b089c50b957a3ab61aeb722ea57dccd9
    - ecl current upstream: https://github.com/PX4/ecl/commit/10a0fef7b7db749f5baf3384e9c900d3aa0e8140
    - Changes: https://github.com/PX4/ecl/compare/f240eaa5b089c50b957a3ab61aeb722ea57dccd9...10a0fef7b7db749f5baf3384e9c900d3aa0e8140

    10a0fef 2018-10-18 jie.zhang - EKF/control: remove unnecessary yaw_align update
8bbaf89 2018-10-17 Daniel Agar - EKF add new simple setIMUData() interface (#512)
e6cd6ef 2018-09-03 Paul Riseborough - EKF: Fix bug preventing  use of flow sensors without gyros
2c3a064 2018-09-18 Daniel Agar - README.md update Jenkins build status icon and url

made changes based on reviewer feedback. Also added a bool option for block_read and block_write PEC, as some devices may not use the PEC

vehicle state.

The hover thrust param also changed the thrust scaling in Stabilized mode.
However if the hover thrust is very low (e.g. below 20%), the throttle
stick input becomes very distorted.

Instead of calling _updateSetpoints(), that also sets the thrust setpoint,
which is then overwritten again.

It's confusing and there is a corner case where the result is incorrect:
*= 0 will not set the variable to 0 if it's already NAN.