Add ability to capture pre/post lowering checks

Related to a feature request on sealog-client-vehicle.

Add a section to the sealog-server API for storing items for pre-check and post-check checklist items.

Add a section to the cruise and lowering records for storing pre-check and post-check checklist results.

Make sure that when a checklist item is updated that the updated cruise/lowering record is pushed to the all connected clients.