Add non diaspora contacts to your roster

It is now possible subscribing to normal jabber addresses
Fixed string merging; '<<' touches also password var
Introducing roster flag to separat diaspora user
Added missing schema tables
Added several test for sql adapter
Fixed roster tests; missing diaspora flag
Enable cross_domain messaging and disabled whitelisting
Accept self-signed certificates
Fixed config and adding non-diaspora contacts to db
Removed whitelisting tests
Check if jid is already known to database
Merge pull request #13 from Zauberstuhl/add_non_diaspora_contacts_to_roster

Add non diaspora contacts to your roster