[INTERNAL] moved GUI code out of the network layer

Made an additional change. Adding someone to the contact list will now
require an additional approval e.g Alice adds Bob:

Before:
Alice automatically authorize Bob when Bob adds Alice

After:
Alice is asked if Bob should see her online/offline status.

Change-Id: I38ec18e109f2c73d61856c56e5ffcc2f148e7842
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/1304
Tested-by: Jenkins CI
Reviewed-by: Stefan Rossbach <srossbach@arcor.de>