Energy beam

Over the last couple of weeks I’ve mostly been doing code cleanup and bug fixes, so there’s not much new to show.  I have added a new energy beam effect though, for when you have a construction selected.  It’s a first stab at it and still needs some tweaking, but it works pretty nicely.  Once I add the construction tool held by the player, the beam will emanate from that, but for now it comes from just below camera.