PX4FirmwarePlugin: Rework flight mode override mechanism

Previous version would require plugin to override all the
isFooFlightMode methods to work correctly. Now just change mode name
and regular plugin code works correctly.

Polygon draw: Fix binding to repeater index

Telemetry logs: Log extension is .tlog, use numeric month in filename

Tweaking Attitude Indicator

Adjusting vehicle icon and making it consistent with Compass Widget

Otherwise things go haywire when points are added

Major rework of polygon editing

Plan: UI Tweaks to plan view editors

Mission Settings: Better visuals for mobile and connected vehicle

Plane: After a remove all leave map position/zoom alone

Better mobile visuals for polygon draw

Move VehicleComponent::prerequisiteSetup method to AutopilotPlugin

Guided bar confirm: Better usability with touch

This makes VehicleComponents reusable from core plugin without
requiring override of prerequisiteSetup

Settings: Default mission item altitude - Fix visibility check

Telemetry logs are now saved with generated file name

No more user prompting

Fixes for using Vehicle Setup pages in core plugin

Correct handling of Advanced mode for App Settings

Automatic sizing support in QGCMouseArea

Plan:Survey: All survey values are now SettingsFacts

New mechanism for better "touch-ability" of controls on mobile