This does the following:
- add RTCMMavlink class that streams RTCM messages via mavlink
- add GPSProvider class that opens a serial device and uses the gps driver
  submodule to get an RTCM stream
- add a GPSManager class that manages the RTCMMavlink & GPSProvider classes
- implement gps driver callback & definitions using Qt
- add the GPSManager to the QGCToolbox

To test this, uncomment the _gpsManager->setupGPS("ttyACM0"); in
QGCToolbox.cc

- Include appveyor YAML script in windows build other files

See also: https://github.com/appveyor/ci/issues/743

* qmake silent build

* Disable silent build on windows

- Convert mission load/save to it
- Allow parameter load/save on mobile

Plus new unit tests

Download Speed Tweaks (+2 squashed commits)
Squashed commits:
[ff0ef7e] Cleanup (remove OpenStreetMap)
[370fa1d] Done (+25 squashed commits)
Squashed commits:
[9f3368f] Need to check how many instances of MapEngine are active.
[d557eac] Download Optimization
[392f50a] Almost there.
Trying to optimize download.
[a49d1d2] Settings
[a94be97] Mostly there. Needs to finish options and map thumbnail.
[38d5a0b] Downloading tiles and deleting sets
[81101b9] More UI Work
[c597d4b] Downloading tiles
[a815e35] Get rid of OpenMaps
[7e177ea] More reorg
[fa6b671] Start handling create tile set
Fix signal order when creating fetch tile task
[2a31f4d] Refactoring
[268b906] Renaming things
[947d66e] Fix resource load error.
[19e2de8] Adding MapBox
[c73e627] Preparing download
[87bbf22] UI Tweaks
[3c32a86] A lot of UI code done.
[ece8ce2] Starting to deal with tiles
[7f387bc] Save tile set
[f66f343] Adding more code
[4de3418] Working
[f0cc25d] Done for the night.
[2d1d86e] Added SQL database for holding out own tile cache.
[d405a87] Convert to camel case as this has been driving me nuts.

Plumb through initial object mode on Vehicle

- override by vehicle type
- override by firmware type

C++2003 didn't had variadic templates so different number of
arguments must have been already implemented in the templates
and since it's impossible to get the amount ot different methods
that paople write, a variadic template was neede.

now we can connect signal / slots with 6+ arguments.
Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>