Added quick implementation for Basic authentication.

Conflicts:
	samples/mail-calendar-contacts-app/demo-app/src/com/example/office/OfficeApplication.java
	samples/mail-calendar-contacts-app/demo-app/src/com/example/office/ui/Office365DemoActivity.java
	samples/mail-calendar-contacts-app/demo-app/src/com/example/office/ui/fragments/AuthFragment.java