Add client background service and CLI

[sndnv]

• [core] - Add API matcher for Instant
• [core] - Add events-based persistence
• [core] - Refactor JWT authenticators/providers
• [core] - Add OAuth2 client with support for client_credentials, password and refresh_token grants
• [core] - Add support for buffering requests in HttpEndpointClient
• [shared] - Remove schedule from DatasetDefinition
• [shared] - Add info to DatasetDefinition
• [shared] - Remove process from Schedule
• [shared] - Remove missed and overlap from Schedule
• [shared] - Add isPublic to Schedule
• [shared] - Add info to Schedule
• [shared] - Rename instant to start and change to LocalDateTime
• [shared] - Add Operation trait
• [shared] - Add Public permission for views
• [shared] - Add salt to User
• [server] - Add support for querying the latest DatasetEntry for a definition
• [server] - Add support for querying public schedules to data store and API
• [server] - Add /service/ping endpoint
• [client] - Add support for tracking operations
• [client] - Add support for scheduling operations
• [client] - Add support for parsing and expanding include/exclude rules
• [client] - Add support for parsing schedule assignment configuration
• [client] - Add support for checking in with server (via /service/ping)
• [client] - Add support for searching in dataset metadata
• [client] - Add support for managing credentials for server core/API
• [client] - Add support for managing config files
• [client] - Add support for recovering files to custom directory
• [client] - Refactor backup and recovery operations/stages
• [client] - Refactor file/metadata collection
• [client] - Add HTTP API for proxying requests to server and controlling client
• [client] - Add support for authenticating HTTP API requests (token based)
• [client] - Add service
• [client] - Add support for buffering requests in DefaultServerApiEndpointClient
• [client] - Add support for caching server API responses
• [client-cli] - Add client CLI
• [identity] - Fix mismatched expiration times between JWT and access token wrapper
• all - Configure logging based on logback
• all - Add 'stasis' prefix to all artifacts and docker images
• all - Update configuration and environment variables

[coveralls]

Coverage increased (+0.01%) to 99.968% when pulling 44b57634400827549ec8b717c7cf050b29ebcf83 on client-add-api into c181cc59727090f330afe6faa4646f256263647e on master.