Add a test for the RemoteCandidatesAdded signal.
Add a test for the RemoteCandidatesAdded signal.

Because of fdo bug #25426, adding remote candidates using the GTalk v0.4
doesn't work if Gabble initiated the call. It can't be tested, so just skip
that mode for now.

jku/telepathy-gabble,jku/telepathy-gabble,jku/telepathy-gabble,Ziemin/telepathy-gabble,Ziemin/telepathy-gabble,mlundblad/telepathy-gabble,mlundblad/telepathy-gabble,Ziemin/telepathy-gabble,Ziemin/telepathy-gabble,mlundblad/telepathy-gabble