Initial commit.
Added code for user to enter text.
Implemented Operation class, and a method to perform addition.
Added more operations to the class.
Subtract, multiply and divide.
Added Menu class.
Moved user menu and reading of user numbers into its own class.
Test commit - no real changes.
Revert "Test commit - no real changes."

This reverts commit eb1ea32d9d50601de9a94aa564f120bbfc18c277.
Took menu text out of its own class.
Didn't seem to compile when inside a class.
Added menu to read user's choice of operation.
Added class to execute operation.
This class takes the user's chosen operation, makes an instance of the Operation class, and returns the result. The code currently test for addition only.
Added code for all menu choices.