Fix display of ZIP code in .ip

freegeoip.net/json returns the key 'zipcode', not 'zip', thus jenni
never showed the ZIP code.
Fix typo in previous commit
Merge branch 'fix-ip-zipcode' of git://github.com/nyuszika7h/jenni into nyuszika7h-fix-ip-zipcode
Merge branch 'nyuszika7h-fix-ip-zipcode'