Change p2p/jingle transfer notification

[sonicnkt]

At the moment p2p/jingle file transfer triggers the same notification as http_upload transfers (file received) as jingle requires user interaction this should be changed to something like "file offered" instead.

[sonicnkt]

Since actions in notifications are supported for other Notifications it would be greate if the notifications could also be extenden with something like this:

Jingle Transfer offered:
example-filename.zip

And the Actions Download and something like Ignore