Adding missing qgcView to QGCMapPolygonVisuals instance in SurveyMapVisual.qml

Instead of hardcoded "QGroundContorl" strings

- Fix imports to support 5.7
- Move properties to correct location

* Add volt/amp calculators

* Correct amps per volt calculation

UI Tweaks for all mobile platforms.

* PX4: Deal properly with optional components

* RC map UI: Offer better defaults and user guidance

all calls to qsTr are done, if I didn't forget anything,
on the PX4 QML files.
Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>

Add scroll height indicators to Flickable