DotList converted to list for proper "in" operation to avoid logging out spurious warnings.

"in" operation for pyon.util.containers.DotList not working as expected:

><> type(instrument_id)
--> pyon.util.containers.DotList

><> instrument_id
--> ['PRE:SBE37_SIM_02', 'PRE:SBE37_SIM_03']

><> instrument
--> 'PRE:SBE37_SIM_02'

><> instrument_id[0] == instrument
--> True

><> instrument in instrument_id
--> False     # but should be True

><> instrument in list(instrument_id)
--> True
remove obsolete parts in test_mission_executive (just keep the unit tests)
remove unused test file
remove temporary more permissive _go_inactive for shutdown sequence in mission manager tests
test_platform_agent renamed from test_platform_agent_with_rsn (mainly to avoid confusion as the tests are against the CI RSN OMS simulator, and not against the actual RSN OMS endpoint)
base_test_platform_agent renamed from base_test_platform_agent_with_rsn (mainly to avoid confusion as the tests are against the CI RSN OMS simulator, and not against the actual RSN OMS endpoint)
re-enable and expand unit tests for RSNPlatformDriver
Merge pull request #2220 from carueda/pa_cleanup_renamings

platform agent test cleanup