use ion.agents.instrument.test.test_instrument_agent.DRV_URI_GOOD as the reference to the SBE37 egg
remove bad reference to instrument_id in log message in exception thrown by IMS.stop_instrument_agent_instance
get parameter dictionary from the stream's stream_def_dict dictionary (instead of directly from the to-be-removed "parameter_dictionary" entry)
Merge pull request #1282 from carueda/master

Fixes and adjustments in platform agent