Merge pull request #166 from frsela/tokens_test_fix

Fixed modify tokens unit test
Changing public key with public certificate URL on NS_UA_WS
Added client certificate auth in AS frontend
Added protection to very big downloads. We only accept first chunk
Simplified certificate check using only the fingerprint
Protect AS to non-client certificate connections
Updated tests & scripts to the new certificate way of auth
Check if no cert found in the DB in the callback method
Simplified the way the notification is checked
More clear way to get the kind of protocol to recover the client certificate