• Update for Factorio 0.18

• Update to use LuaRendering objects rather than entities. Among other things, this means that displayed text for
  rail distances should only be visible to the player hovering over a signal.

Updates for Factorio 0.17

• Hovering over a signal now shows the distance to the closest next and previous signals. This should be useful when using long signal distances with the related signals being off-screen.
• Fixed a bug when placing signals would fail due to the presence of a signal ghost, which would cause another signal to be placed immediately after it.
• Signal ghosts now count as signals.

First release!