Add scroll height indicators to Flickable

Everything is now based off of default font pixel size

If Facts are referenced from FactPanelController, we need to reference
count the AutoPilotPlugin such that it doesn’t get destroyed until
after the FactPanelController is destroyed.

- More more on making QGCView real
- Converted Parameter Editor to QGCView

- You can now cancel parameter change
- Tablete friendly