Support loading id, gid and root_gid for attributes in remove relationship edits
Support saving id, gid and root_gid for attributes in remove relationship edits
Link relationship edits to instrument edit histories
Add a basic entity_gid property to create-type edits and populate it with Edit::Role::Insert
Also add MBIDs to basic Edit-type edits
Support loading id, gid and root_gid for attributes in remove relationship edits
Support saving id, gid and root_gid for attributes in remove relationship edits
Merge branch 'basic-entity-mbid-edits'

* basic-entity-mbid-edits:
  Also add MBIDs to basic Edit-type edits
  Add a basic entity_gid property to create-type edits and populate it with Edit::Role::Insert
Load attribute and attribute-root GIDs in Data::Link
Merge remote-tracking branch 'nikki-bitbucket/store-ids-remove-relationship'

* nikki-bitbucket/store-ids-remove-relationship:
  Link relationship edits to instrument edit histories
  Support saving id, gid and root_gid for attributes in remove relationship edits
  Support loading id, gid and root_gid for attributes in remove relationship edits