Relation annotation: hairball alert

[rsimon]

At the moment, Recogito will show all relations, on all annotations. Obviously, not a huge problem during the (alpha) test phase. But we need to change how this is displayed.

Essentially, it was the plan from the very beginning to not show links, but only some sort of indicator that there are links on a specific annotation. Then, when selecting the annotation, the links should be rendered only for this annotation.

[rsimon]

And/or: clicking an annotation could highlight the connection from/to it in different colors.