v0.0.0.44 - Refinery added & workers haul

We have a new build item, the Refinery :o) Now your mined ore can be processed into more metal for further construction. 

Worker bots, now haul ore to the refinery or storage from the mining unit, and processed metal gets hauled to the metal storage units.

Lots of little fixes and improvements as well under the hood:-

• Few additional checks so material limited by capacity (could previously mine more than you had room for). 
• Worker droids are now animated (was in previously, but hadn't set them!). 
• Played around with a shader, so rooms are 'lit' when you are generating power (thought it's a nice visual indicator). 

Next up, I guess these metal storage units should be where workers go to collect building material before constructing anything, so that be my next focus, and improving the bots behaviour.  May also add a droid maintenance bay, if that makes sense, whilst looking at droids.