Xtrabackup manager for kewpie

This blueprint describes the xtrabackup manager module to handle all MySQL backup tasks within kewpie framework.
The module should provide methods to create all types (full, incremental, partial) of backups from server objects (class server) and be able to handle restore tasks (prepare and restore backups, import individual tables).

Methods:
 - full backup
 - inc backup
 - restore backup to a given server object
 - clone server from backup (create new server object)
 - export table to a given server object
 - manual - manual processing of backups

At the same time it should allow to handle backups manually, providing custom options and commands to xtrabackup/innobackupex.