Include "assays" in JSON format

[aclarkxyz]

Forgot to mention that. We should add an additional section in the JSON schema format for "assays":

    ...
    "assays":
    [
        {assay1},
        {assay2},
        ...
    ]

It would be OK to make it omit this section if there are no assays associated with the schema (which is the case for schema.json). Parsing a schema should interpret absence of this section as no assays.

[gedeck]

What is the use of this section?

[aclarkxyz]

The template editor is actually also an annotator, albeit a crude one. It's a bit rude to stop saving this information after changing the format. The reason I want to bring it back is that when we start creating "fragment templates", we may want to populate some of them with default values. This would be an ideal place to put them.

[aclarkxyz]

Don't implement this yet... the data model for curated assays has gone stale, and needs to be freshened up.