[Contacts rewrite] Unify storage API

[rfc2822]

So that it has the same architecture as events and tasks

• Deprecate AndroidAddressBook in favor of new AndroidContactStore (takes Account as argument)
• CRUD for raw contacts (as Entity) in AndroidContactStore
• CRUD for groups (as Entity) in AndroidContactStore
• CRUD for high-res raw contact photo in AndroidContactStore
• CRUD for settings in AndroidContactStore
• CRUD for data class ContactAndPhoto(val rawContact: Entity, val group: Entity, val photo: ByteArray) in AndroidPhotoContactStore that decorates AndroidContactStore (similar to AndroidRecurringCalendar that decorates AndroidCalendar). Mapping will then between vCard ↔ RawContactAndPhoto