feat(datastore/dataobject/mappingTable): Add mapping table for datastores
and dataobjects

- all datastores are shown in a mapping table on the definition tab of the
  properties panel
- all dataobjects are shown in a mapping table on the general tab of the
properties panel
- it is possible to add and remove a datastore/dataobject
- a confirmation dialog is shown for deletion

related to #CAM-1363