fea. Add ways to insert point between missionPt and geofence points

[tbkoay]

Currently state:
We add new points to the end of the list. We add a point at the end and rearrange existing points to effectively do an insert.

Expected outcome:
One can insert point directly.

• missionPoint in mission planner
• geofence creation and editing

Suggestions:

• on map: make use of the line object between the points to find out the position of new point in the list
• on the mission panel: use the position of the list