Added bill for Customer Sub Transaction
Removed class
Merge pull request #19 from ellina-s/arjan

Arjan
I think customer sub transactions are finished.
Renamed test set
Merge pull request #20 from ellina-s/arjan

Arjan
Finished the getPurchase method
commented out line
Merge pull request #21 from ellina-s/arjan

Arjan
Merge pull request #22 from ellina-s/clark

Clark
Implemented getLeadSinger 2D array
Implemented getting 2D array for HASSONG
Implemented Customer Registration and added test for it
Refactored Customer Registration and test for it
Implemented Customer Authentication function. Added tests
Added more tests for authentication and refactored some code
Finished Manager Transactions, update other files
Split Purchase transaction into steps
Add Items Transaction

Add Items transaction for managers complete
Fixed bugs in ManagerTransaction completed clerk