PayOnlineSystem Integration

Created models and service methods to integrate with PayOnlineSystem.
Demonstration in HomeController.cs > PayOnlineSystem().
CreditCardsSystem Integration

Implemented CreditCardsSystem service and added models.
Response Code Updates
Correct .csproj
Merge remote-tracking branch 'origin/integration1' into complete
Merge Integration2
Merge Conflicts
Merge branch 'complete' of https://github.com/jeffodle/bookstore into complete
Merge Conflicts
Merge remote-tracking branch 'origin/complete'