Closes#729
1. Dark mode now applied correctly (was previously lacking)
2. Fixed terrain brush action (brush active is higher priority than drag, fix tile fetch)
3. Fixed writing of Building/structure labels; apply after Terrain
4. Single terrain brush form allowed, center to Field Editor on launch
Somewhat related: fix Show() load for non-ShowDialog() forms to center to parent.
* Added new image code, quanted existing images, fixed bcsv parser
* small clean and sane(r) filenames
* Made a string slightly nicer
* various revert to fix diff
* full revert of editor
* forced revert of editor
* fix sprite init
* ready for merge
