Added Parse framework support
Introduced authorization manager
Fixed keyboard not showing properly in Sign Up view
Implemented authorization with Parse
Implemented signup with Parse
Implemented finding account by email
Implemented notification-based system
Refactored sign up procedure
Implemented loading of user info when she logs in
Implemented user log out
Fixed switching between users
Merge commit 'e8de4ad' into develop
Implemented saving and loading of user photo
Implemented sequential switching between text fields

That is, when user taps Return, the focus now switches to the next text
field in view and automatically hides keyboard after the last one.
Automatical calling a default window button event isn't implemented yet.
Implemented return to login screen when after pasword restore
Refactored setSettingsWereModified into a property
Fixed ImagePicker not closing on Cancel tap
Added user photo and user name to chat with friend
Refactored switchToTab method into a property
Fixed user photo not appearing in first chat message