Refactored hopBill object out of hopBillController

* Now a the hopBill controller just needs a hopBill
* HopBill ensures all hops are contained and have correct methods
* Need to fix all the demeter violations
Abstracted the implementation of flavor hops a little
Cleaned up hopBill

* Move functions to the prototype
* Removed private variables
* Added getBitteringHopIbus method to bittering hops