Core: redesign Property API

[jri]

Topic/Association? properties should be accessible without obtaining the Topic/Association? object in advance. The Topic/Association? ID should be sufficient.

This is required in conjunction with #668 (and thus #592). Furthermore it improves performance.

[Jörg Richter]

Get property w/o fetching the object first (#669).

The DeepaMehtaService has 2 new methods:

Object getProperty(long id, String propUri)
boolean hasProperty(long id, String propUri)

They access a Topic/Association? property without obtaining the Topic/Association? object in advance.
The id is a Topic ID or an Association ID.

BREAKING CHANGES

The DeepaMehtaStorage interface has changed, so storage layer implementations must be adapted.
The Neo4j based implementation is adapted.

See #669.

• Changeset: 45a38ce791de4b1bef67b70ec2b81e1c77b34e28
• URL: ​https://github.com/jri/deepamehta/commit/45a38ce791de4b1bef67b70ec2b81e1c77b34e28

[jri]

Realized in workspace-acl branch. Will be available in DM 4.5