DLINE <time> <nick|ip> :[reason]

<time> if present, gives number of minutes for DLINE

Adds a DLINE which will deny any connections from the
IP address of the banned client. The banned client will
receive a message saying he/she is banned with reason [reason]

In order to use <nick> rather than <ip>, <nick> must
be on your server.

- Requires Oper Priv: dline
