Some new server to add to the registration list

Problem

Some good XMPP servers are missing to the registration list in Gajim ;)

Analysis

Add the servers below:

Enhancement recommendation

Add these servers:

• im.jappix.com
• neko.im

Thanks!

I thinhk it would be good to do some cleanup in this list, and we should use the list maintained on xmpp.org: http://xmpp.org/services/

(In 76962db8) update servers.xml from xmpp.org. Fixes #5797 (closed)

(In 971843ff) update servers.xml from xmpp.org. Fixes #5797 (closed)