This closes out all value editing before the new item is added. Fixes
the bug where you enter a new altitude in last waypoint, don't press
enter and then add a new one. In that case altitude would be set after
new item was added. Hence it would not carry to new item.

Should be all working now except for distance < radius cases.

Previous version would require plugin to override all the
isFooFlightMode methods to work correctly. Now just change mode name
and regular plugin code works correctly.

Otherwise things go haywire when points are added