     Syntax:   MODUSER #Channel ADDMASK <IDNick> <nick!user@host>
     Use:      Associates a hostmask with a partcular IDnick
     Example:  /msg \n MODUSER #Channel ADDMASK Bob somenick!*userstuf@*.myhost.com
     ----------
     Suggested Use:
     ----------
     Used to add a nick!user@host mask to the user's mask list
     for authentication purposes. The user must authenticate
     from a host on the list in order that the authentication
     be successful.
