Track and route editing — Steam Revolution: The Age of Rail Steam update #47420

Added button to remove all routes from the selected set, indicated by a nuclear mushroom cloud icon.Added button to heal track, removing a "cut". This replaces 3 connected tracks with a single track.Fixed bug where deleting a route from an unset signal didn't populate all the other routes at that signal like it should have. This was a regression from how it worked before.Fixed bug with track highlighting going past one way signals that face the wrong direction. Calculate and store route highlighting on a per segment basis instead of per track.Made route highlighting calculations use a bitmask for a bit better efficiency.Made route destinations always show, even when the source signal isn't selected, but in a more muted color. I made the selection color bright white to compensate to be more visible.Better sanitization of strings to have a filename-safe encoding. I now allow spaces and oth...