Status of three annotation types in discriminator file

[marcverhagen]

There are three annotation types defined in lapps.discriminators (Chunk, Lookup and Matches) that are really defined as elements of the vocabulary but not quite. They have vocabulary-like URLs but are not displayed in the vocabulary and no properties are defined for them (and it looks like that is impossible in lapps.discriminators).

The special status of these needs to be motivated and documented.

[ksuderman]

These are annotation types produced by GATE and were included in the list of discriminators before we had a formalized vocabulary. They can likely be marked for removal as discriminators or repurposed if we can find a use for them.