some clean-up and comment update
include provider_id (from org_obj._id) and actor_id in configuration
IMS: pass agent_id from context to the configuration in start_platform_agent_instance
pass get_system_actor_header as headers argument in IMS.start_platform_agent_instance and IMS.start_instrument_agent_instance calls
initial version of exclusive access for mission execution
release associated commitment when exclusive access to a resource is not needed anymore
cancel start of a mission plan when an exclusive access request fails; all others that have been successful are reverted
Merge pull request #2146 from carueda/pa_mx_exclusive_access2

M101: exclusive access for mission execution