- Added a layer selector
- Added a line tool
- Changed the fill tool to stop at blocking terrain, when filling with
something other than terrain
- Updated the rotate tool to respect the layer selector
- Updated the adjust tool to respect the layer selector
- Added support to the adjust tool for railroad tracks, ice, swivels,
force floors
- Restored the adjust tool's support for buttons, added a pressed-button
preview, and added support for blue buttons
- Added an ice tool, for drawing ice corners interactively
- Added a text tool, for writing longer text via letter tiles
- Added a thin walls tool
- Changed the wire tool to draw wires for more types of mouse movements,
so that any kind of scribble should produce a continuous wire;
individual clicks will also place a wire immediately
