Schema: Add form-based schema definition for create/update/revise

[dvstans]

Currently, the schema editor uses a third-party JSON editor. An option should be provided to view and edit schemas using full GUI form editor. Need to investigate if any existing JS libraries are available for this, and if not, create one. The form should be JSON schema aware rather than a generic document editor (i.e. create properties, fields, types, references, etc.) For reference fields, a schema pick option should be provided.

[dvstans]

Note: the technology supporting this UI should also be capable of supporting schema-based search forms for data records, as well as editing metadata in data records.