Errors and enums

EGraffityARErrorCode: None, InvalidConfiguration, InvalidState, UnsupportedPlatform, CapabilityUnavailable, CameraInUse, Authentication, Network, InvalidData, Cancelled, MissingRoot and DuplicateRoot. FGraffityARError contains Code and a fixed safe Message. Permission includes Unknown, NotRequested, Granted, Denied and Restricted; Android Unknown cannot distinguish first request from denial. Read current capabilities before recovery rather than guessing permission status.