- Also renamed QGCCore->QGCApplication to better reflect usage.
- New global qgcApp api to access main QHCApplication singleton

Make sure to no de-reference already deleted object

Also renamed from QGCSettingsWidget to SettingsDialog to better reflect
usage.

This avoids collision with main app SettingsDialog class

Centralize all connecting and disconnecting of links through
LinkManager::[Connect|Disconnect]Link api. Connect/Disconnect no longer
allowed through LinkInterface. This allows creation of new
LinkManager::setConnections[Suspended|Allowed] methods to disallow
connections as needed.

Map widget: make all connections that might suffer from multiple connect logic issues unique, found by Nyaruko

This way OS X correctly positioned menu items

This allows you to filter the list of parameters the widget displays.

This allows you to determine if full parameter list is ready if you
missed the parameterListUpToDate signal.

Also fixed bug in loadStyle

Prepping for stable 2.2 release

The dark css is the master and contains all style information. The
light css is the slave and only contains color information.

This allows you to filter the list of parameters the widget displays.

This allows you to determine if full parameter list is ready if you
missed the parameterListUpToDate signal.

Handy for testing without a real board