some small change
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.
Merge branch 'master' of https://github.com/nwunder/JUnit
Merge branch 'master' into nathan
Revised Dollar and Cents Value functions (Cents returns justthe cents over the dollar)