User Resync

When a user with a known username connects to VBAN-M, VBAN-M asks the client of this user for his identifier (Refer to #5 ), if the identifier already exist in the database, VBAN-M will replace the old user by the new one by changing its IP address in the database.

&#9888;&#65039; Subject to changes for security issues &#9888;&#65039; 