PHP ICQ: Communicate with ICQ users

This class can be used to communicate with other ICQ users.

It can:

- Establish connections to an ICQ server using non-blocking sockets
- Authenticate as a given user
- Receive offline messages
- Send and receive messages
- Send contact authorization requests and acceptance messages
- Check invisible status
- Set the user status and status flags
- Manage contacts and receive contact user online status notifications
- Manage private user lists
- Get and set user information and password
- Search users by several criteria
- Register new user account
- Generate debug and error information
- Trigger connection events and execute event handling code