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.

Plus remove unused code

Also added ui support for multiple complex item types

Allow plugin to define default font size, toolbar height and option to display/hide plan view selector.

- Shot Interval in Survey
- Much change to time/distance calc

This makes text show up better on map images

Shows horizontal/vertical scroll indicators