Some smaller UX improvements

Initial Structure Scan support

Solve some typos

tools: Remove fix_code_style.sh

Add JSON key for mobile-specific default values

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Fix current mission item updates

No one is using it.
Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

MissionItemStatus: Make waypointValuesDisplay with variable width

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Fix Mav2 handshake

FlightDisplayViewWidgets: increase the maximum widget size from 200 to 400

Fix joystick tx mode initialization

Update MissionController.cc

Still does not support multi-vehicle

On large/high DPI screens, the whole UI scales nicely when increasing the
font size, except for the attitude widget, that was limited to 200 pixels.

Allow resizing pip window

LogDownloadController: only skip entry if size==0 && APM firmware

save to kml use double number with 10 valid digits。

Update joystick mapping database

Make FTP more robust

Move to Qt 5.9.1

Assume all vehicles support MANUAL_CONTROL

On PX4, under certain circumstances and in rare cases, there can be log
files with 0 size. In that case QGC ignored the entry and tried to
re-request the entry indefinitely.

mobile needs more testing before we can enable this.
A test on an android phone was successful however.