OOIION-1095: New test_13_platforms_and_1_instrument, 

https://jira.oceanobservatories.org/tasks/browse/OOIION-1095

test_13_platforms_and_1_instrument is the same as the failing test_13_platforms_and_2_instruments, but only with one instrument and it runs fine even --with-pycc,
so the problem seems related with the launch of multiple port/instrument agents.

Needs more investigation but please merge so we can verify the new test on
the buildbots.