minimalRemainingMissionTime added to General Settings, and Low Battery Handling on small minimalRemainingMissionTime function added

WimaController MissionController WimaDataContainer WimaPlanData WimaPlaner reset to ae16d99f, and centering of flight map after mission upload (wima menu) improved (centering only if map not centered to vehicle)

insertSimpleMissionItem(const QList<const MissionItem *> &, int) and _initVisualItem(VisualMissionItem*, bool) added to MissionController