Added "msgpack" library
Created new "plugin" module under [/Libraries/Shared], moved "Environment" class to "plugin.core.environment"
Moved "sync.manager" to "sync.sync_manager" to avoid conflicts (plex-specific issue)
Removed unused imports in "sync.sync_base"
Implemented new module system (outside of the plugin sandbox)
Initial implementation of trakt.tv data backups
Split backups into separate files for each flag (collected/rating/watched)
Increased max delta chain from 20 to 50
Added placeholder for "collected_at" timestamps (defaults to 0)
Pack "movie.is_watched" into a _Bool
Re-ordered rating struct packing to match other attributes
Merge branch 'feature/automatic-backups' into develop