Make a test connection to determine NAT type

Make a test connection to the symmetrically NAT'd probe site to
determine NAT type. This replaces the previous method of getting
ICE candidates from two different STUN servers and more
definitively determines compatability with a symmetrically NAT'd
client.
1 job for issue/snowflake40013 in 2 minutes and 57 seconds (queued for 53 seconds)