Strip spaces in nick/host lookup

[khaytsus]

When doing /nick_lookup partial(tab) irssi automatically puts a space at the end and that is passed into get_nick_records with a space in the $query string and so it fails. I have locally used a regex to strip out the trailing space with $query =~ s/\s*$//g; but there could be better ways to fix this issue.

[IsaacG]

6baba20
This needs reviewing, the "changed" date updated, VERSION bump and a changelog entry before going into master

[khaytsus]

Thanks :-D