Display friend's avatars on Dashboard even when they are offline

* Fixes TWK-398
Automatic merge of Transifex translations
* Some fixes to InfoSystem and loading.
Add missing emit ready()
Revert "* Some fixes to InfoSystem and loading."

This reverts commit 8460d8f5227e889f10805a9af87851ce654ec460.
Revert "Add missing emit ready()"

This reverts commit cc336e9d45f1f466251a43696c8a9417d0d272bf.
Servent should listen to IPv6 too
Change option description to reflect new functionality
Support multiple SipInfos per peer
Remove asserts in getters as this makes debugging harder
Always return SipInfo, even if not visible
Create SipInfo with the correct information.
Ignore Zeroconf messages sent by ourselves
Get back accidently deleted registerOffer
Better way to get the id of a peer
Rename sipInfoList to sipInfo
Add missing writeEndElement
Ignore IPv4 localhost even if written as IPv6 address
Do not try link-local addresses.
Correctly ignore IPv4-as-IPv6 localhost