Allow backwards compatability for mods which have not updated their ISidedInventory usage, until Forge drops its deprecated version
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 #120 from Tallinu/master

Merge adjustable transformer, test build