CE-1019 changing user data create to update with fallback to create if doesn't exist
CE-1019 use WikiaLogger, use BaseTask, register autoload API classes
CE-1019 getUserEmail and prepareUserRetrieveParams
CE-1019 Delete task: Run delete request to delete email from subscriber list
CE-1019 retrieveUserIdsByEmail refactoring
CE-1019 Minor variables names refactoring
CE-1019 Adjusting user hepler prepare params method to return format required by API
CE-1019 Adjusting prepare user delete params
CE-1019 Adding subscriber create to the task
CE-1019 Move retrieve methods from delete task to retrieve helper
CE-1019 Removing unused methods