No network leads to crash

[mmalte]

By mistake i used kontalk.halifax.rwth-aachen.de as manual server address instead of kontalk.net|kontalk.halifax.rwth-aachen.de

This led to a crash when writing a message, refreshing contanct list and some other situation.

Maybe add a warning that the server address is not valid or switch to two fields, one for the network and one for the server.

[daniele-athome]

Thanks, I'll add a regex parser for the moment. I will then add two input fields for both the network and the host name.