Annotations: add query support for reverse meta annotations

If 'annotates' fields are found in the parameter dictionary, they constrain the
query by only allowing annotations in the result that are annotating the
entities in those fields.
Annotation navigator: support 'annotates' query in annotation node

If one selects an annotation in the navigator, one is presented an
annotation node. This node provides options what one can do next, based
on the annotation chosen. With this commit a new option is introduced:
'Annotates'. When selected a new annotation list node will be displayed
that shows only annotations that are annotated with the last annotation.

Vice versa, the 'Annotated with' option, will only show annotations that
are annotating the currently selected one.