launch script for jmavsim failed to start if there were any spaces in
paths, string handling in paths was improved and tested.

*  a request for setting the '_HASH_CHECK' parameter is handled differently
than the same request for a standard parameter. Make sure we don't actually
try to set the parameter.

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

Co-Authored-By: CUAVcaijie <caijie@cuav.net>

 - keeping nuttx and armhf compile jobs on 2018-09-11 for now

    - Mavlink v2.0 in PX4/Firmware (d1dc8e440912e7918465163195b73531138e1e8c): https://github.com/mavlink/c_library_v2/commit/6203e2b64395cfa416b9321f633bc3256a79f722
    - Mavlink v2.0 current upstream: https://github.com/mavlink/c_library_v2/commit/7c47254ddc8bf70eb5e82b4c2142a3faa4fa5780
    - Changes: https://github.com/mavlink/c_library_v2/compare/6203e2b64395cfa416b9321f633bc3256a79f722...7c47254ddc8bf70eb5e82b4c2142a3faa4fa5780

    7c47254 2018-11-21 PX4BuildBot - autogenerated headers for rev https://github.com/mavlink/mavlink/tree/aa72b9e9806854ee822eb2fb4c70c26216113141

You can now add `DYNAMIC` as an option to `px4_add_module`, which will
cause that module to no longer be compiled into the px4 executable, but
instead produce a separate shared library file, which can be loaded and
executed with the new `dyn` command:

    pxh> dyn ./hello.px4mod start

This will load the shared object file `hello.px4mod` if it wasn't
already loaded, and execute its main function with the given arguments.

The threads running commands for clients through the Posix daemon used
to write to a char buffer through snprintf (etc.) which was then written
directly to the file descriptor, whereas in the other case printf
(etc.) was used to write to stdout (FILE*). Both versions used some
macro's and repeated code to have the same output.

This change unifies these two cases by using a FILE* in both cases. The
(line) buffering is done by the standard C library's implementation
(just like with stdout), and px4_log.c now uses the same code in all
cases (using fprintf, etc.) for printing (colored) output.

 - fixes #10896

* attitude and rate setpoint message: use 3D array for thrust demand
* FixedWingAttitudeControl: rework airspeed scaling
  * move airspeed and scaling calculation into separate method
  * if vtol in hover and airspeed disabled use minimum airspeed instead of trim airspeed

Because it was always failing from the beginning on and
we want to make sure no other tests break in the meantime
by running the currently passing tests also on Windows CI.