#1603 All messages go to server buffer when no nickname specified

[Alex Jordan]

Steps to Reproduce:

1. Open XChat 2.8.9 on windows 8.1
2. Network list window opens automatically
3. Add a new network pointing to a ZNC bouncer (version 1.4)
4. Set username to <username>/freenode and real name to <first> <last>
5. Add no nicknames
6. Connect to server

Expected Results:
Two tabs are opened, one for the server buffer, and one for the #cyanogenmod channel which I am logged onto on ZNC.

Actual Results:
Messages from #cyanogenmod channel were displayed in the server buffer.