Auto mission assistant

[TShapinsky]

Revised:

TODO

• make next, previous, and restart, function after mission is completed

[m4gr3d]

@TShapinsky the LinearLayout children should have the layout_weight attribute so they can stretch to fill out all the space within their parent is necessary.

[m4gr3d]

Items left to do for this pr:

• Split the mission assistant control bar into two: First part contains the pause and restart buttons; second part contains the skip waypoints bar with the option to enter the waypoint number to skip to.
• On mission start, update the mission items graphical representation with the waypoints making them. (dependency on 3DR Services mission api update.)
• Add OnMarkerClickListener for mission item markers, so that on click, a tooltip shows up with the option to jump to that mission item.