log console_output when test_network_basic_ops failed

For trouble shooting network connectibility check,
This commit add console_output log

Change-Id: I77826970d397b12ee5945a7ed9d68f1de863b9bc
Related-bug:1265495
trusts API test, avoid creating duplicate user

We currently call create_trustor_and_roles twice, in the base
class and the test class, which is wrong and results in the test
leaving a user behind which is not cleaned up.  So only call it
in the test class, because we need self._interface to be set.

Change-Id: I9b96ae4435714d17bfd2b0b2abe570d98e61bfa6
Closes-Bug: #1267704
Merge "log console_output when test_network_basic_ops failed"
Merge "trusts API test, avoid creating duplicate user"