Added Contact.cs, Entity.cs, User.cs

Abstract class Entity.cs
Holds: first name, last name, email

Derived Classes:
User.cs - Calls superclass constructor.
No additional methods or fields yet.

Contact.cs - Calls superclass constructor.
Holds:
bool SentPrevious - determines if a previous email was sent to the user
by this contact.
Minor cosmetic changes. herpderp

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fixed Email property bug in Entity.cs

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added public to class declaration for Contact.cs

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Added Password field and Property to User.cs

As per Nate's request.
added overloaded constructor for password User.cs

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Added Uml diagram for entity class
Add NetworkManager to project
Update UML diagram for Entity heirarchy

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fixed conflict in HolidayMailer.csproj
Merge branch 'master' of https://github.com/ParkChristopher/bitsbeflippin-holiday-mailer into sami

Conflicts:
	HolidayMailer/HolidayMailer/HolidayMailer.csproj