Streamside

The following features are added:

* The command option to select the annotation schema is changed from `-m` to `-s` to avoid a potential confusion.
* StreamSide guidelines are added.

The following features are added:

* The annotator displays cyclic relations correctly.
* Arguments are sorted by their token positions (previously sorted by labels).

The following features are added:

* Word alignment annotation in the Penman format can be read by the annotator.
* When creating a relation, the referent checkbox in the `RelationDialog` gets automatically selected for child concepts that already have parent concepts.
* Text spans can be added or removed for existing concepts.

The following features are added:

* JSON to Penman converter
* In the AMR mode, the relation input dialog now displays the argument structure of the parent concept if it is a predicate.

This version provides the following features to annotate both WISeN and AMR:

* Create concept
* Create attribute
* Create relation
* Delete concept/attribute/relation
* Update concept/attribute/relation
* Save the annotation in JSON