[Feature 1] User Registration

[Madhavan7]

Feature that supports user account creation.

[Madhavan7]

Factory Design pattern was used in order to create objects that deliver the verification code(i.e objects that implement "ISendVerificationCode") - in order to allow for multiple streams of verification

[Madhavan7]

Used Façade design pattern in UserExistsInteractor, so that the responsibility of creating and sending the verification code is now deferred to a new class

[Madhavan7]

Tested the main use cases, used in this issue, such as the classes "UserLoginInteractor", "UserExistsPresenter", "UserVerificationPresenter", using anonymous classes whenever these objects depended on an interface. UI's were tested manually. "UserChatsPresenter" was not tested since it was just a bunch of getter and setter methods

[Madhavan7]

Implemented features so that now the User can login if they have forgotten their password(changes are in the main branch). MVP architectural pattern was chosen for implementing this use case. Fixing code smells, and other minor changes still need to be made. The following files were added(in the main branch): ForgotPasswordScreen, ForgotPasswordPresenter, and the interface RetrieveEmail

[Madhavan7]

MVP was the architectural pattern of choice, since the use cases did not use any complicated data structure, so there was no need to have controller objects