1. Added precautionary tolerances to all double-double comparisons (from a < b to a-b < EPSILON for some tolerance level EPSILON)   2. Rearranged all references to different coin types to put dollars - the largest values - at the front rather than at the back (adjusted the tests to fit)   3. Changed variables to avoid multiple variables called 'value' or 'values'.   4. Adjusted the Envelope Comparison tests: -1 should mean less than, and +1 should mean greater than, right?
Added integer-returning getValue functions, for Cashier's use
Added skeleton for Cashier and the exception class - put in tests for the Cashier Test - corrected spelling of 'nickel'
Small edit to Negative Balance Exception
merging nathan into master
refactored addMoney to match params of takeMoney...all tests pass
all tests pass for Cashier. need to work on the exception now
exception class written. exceptions thrown correctly but tests dont pass yet.
fixed output from neg exception was off by a factor of 100