Usage: sendtextmessage targetmode={1-3} [target=clientID] msg={text}

Sends a text message a specified target. The type of the target is determined 
by targetmode. 
Available targetmodes are:
1: Send private text message to a client. You must specify the target parameter
2: Send message to the channel you are currently in. Target is ignored.
3: Send message to the entire server. Target is ignored.

Example:
   sendtextmessage targetmode=2 msg=Hello\sChannel
   error id=0 msg=ok