Refactoring power functions

[y0014984]

A refactoring on power functions would be helpful. Unfortunately, there are for example some variables indicating a generator but instead this var means beeing a power device connected to a generator, for example in fnx_initPowerInterface.sqf

Every time I read that code my brain get's problems. So for future enhancements a refactoring would safe a lot of time understanding what's going on.