Add control to set flight duration (which ultimately sets the end_time of flight)

Handle flight start/end time
Handle start/stop traffic monitor
Only start telemetry if enabled
Added a "Now" button for the flight start time
Collect advisories only when the rules change

This is in addition to the existing text edit control.

More clang warnings cleanup

Updates in general was only done if a POI changed. This caused changes related to something other than a change in POI to be ignore. The code now "resets" the POI when such changes occur (change of ruleset for example).
Ruleset selection is was not persistent. When reloading the list of rulesets for a given region, any previously selected ruleset would be reset to defaults.
Also fixed several new clang warnings.

It seems the icons now use dash instead of underscore. I'm simply replacing dash by underscore wholesale (to match the existing resource names) until I know better.

Fixed issue where the "Set Circle Radius" menu entry was trying to affect the visibility of an item within a component.

This way you can click anywhere

* Load Plan
* Save to KML
* Load Plan (it tries to load KML instead)