Begin implementation of textured terrain. Rework map editor interface.
Remove UID idiocy from Tile management.
Reworked API in BTMapEditor::Toolbar and its tabs.
Small TileManager fixes...

- Use QPoint instead of QPair <int, int> for hex coordinates.
- Add public tile(const Hex *) static method.
Add tile placement to BTMapEditor.
Fix naming and style to make Fynx happy.