ISServiceLog; obsoleted PurgeAction values now reset to "None"

Service Logs include a special "Purge Action" flag. Several purge actions haven't been used for many years, and so any Service Logs using them have been reset to "None", i.e., don't purge.

Actions updated include "Request", "Response" and "RequestAndResponse". These would remove the Request and/ or Response details from the Service Log and were intended to be used when disk space was much more expensive.