Separate Layouts and Maps

[garakmon]

Feature-complete. In need of cleanup and testing.

Internally removes Layout related code from the Map class. Creates a new layout-only edit mode. Adds ability to modify map groups.

closes #182 closes #477 closes #181 closes #334 closes #548

TODO:

• [x] Edit history in timeplapse replays both layouts and events ~~in order of edits made~~
• [x] Add new map group & map section & layout without map + delete all above + #550 +rename
• [x] ScriptUtility::setMainTab(int index) consider edit mode
• [ ] reassigning layouts silences "Setting Map" message log
• [x] toggle view on empty folders in mapList (map sections, groups, layouts)
• [x] number map sections?
• [x] fix all scripting API functions
• [x] rearrange map groups?
• [x] drop gMapGroup_ prefix requirement for map groups
• [x] use NewMapPopup::initUi where needed
• [x] [BUG] switching to "Connections" tab disables map edits permanently
• [x] Fix loading recent map except it's a layout
• [ ] ~~Rearrange and rename map sections?~~