Update edit field endpoints

[cjmyers]

The edit field endpoints have a few more possibilities:

remove field - title, description, wasDerivedFrom, annotation
add field - wasDerivedFrom, annotation
edit field - annotation

To support annotation, there is now a "pred" parameter for the predicate for the annotation, which should be provided for all remove, add, or edit when working with an annotation.

[jvscholz]

updated

https://synbiohub.github.io/api-docs/#edit-field

[cjmyers]

Let's change pred to:

A predicate for an annotation.

You can drop the only valid for, since it is likely obvious from the definition.

[jvscholz]

updated @cjmyers

[cjmyers]

Looks good. Closing.