Feng-Zihao

Fix infinite loop and nonType bug.

1

1, it's a logic bug in stun_test 2, there're stun implementation which do not have 'changed address' attribute in response. In this case, there's not enough evidence to judge NAT...

Logic error in handling error response

2

in the logic of stun_test, there's code as below around line ``` # around line 113: recvCorr = False while not recvCorr: ``` ``` # around line 136, bind_resp_msg =...