Added basic form of Adjustable Transformer
Also code cleanup including more defined constants
AT is functional but needs more work:
1. Configurable input/output sides (must-have)
2. Independent output settings per side, if possible?
Expanded AT GUI to include directional IO buttons.
Button states are synchronized client-server and properly saved/loaded.
East/West labels mixed up
GUI settings now control energy I/O directions
Adjustable Transformer block textures update (slightly) based on side I/O setting
Minor cleanup
No need to return a surplus on this machine
Merge branch 'features'
Merge pull request #119 from Tallinu/master

Merge adjustable transformer