Added test for interestRate()
Refactored tests
End of episode 4 - [FAILING]
Tracking total withdrawn
Principal never goes below 0
End of episode 5 - Fixed multiple withdrawal
Added getter for totalWithdrawn
Added capitalGainsWithdrawn
Replaced construction parameter capitalGains with startingPrincipal
End of episode 6
Paying taxes on withdrawal for taxes
Split test class
Calcuation interest earned
Incurred capital gains tax earns no interest
More refactoring