Work for Objective 1 and Objective 2

[NicholasBambury]

Extended Offer functionality to enable buyer to view status of offers made

Added new feature to enable buyer to book viewings of properties

Refactored code after initial commits.

[NicholasBambury]

Initial code for objective 2 was created originally in wrong controller. Separated it out into a new Viewing controller as part of 3rd commit to refactor the code.

Observations made of the existing code:

• Possibly split out some of the code into separate Repository area from the Controllers, Builder/Handlers, to handle all entity frame work calls.
• Error Handling and some useful logging should be added throughout the solution.
• Current solution does not have unit tests to cover all Controllers.
• Code clean up, remove all unused using directives.
• Summary comments added to public controller classes/methods would be useful