Integrate new Data Package v2 features

[ezwelty]

Data Package v2 introduces some new features. See the Changelog. Once they are supported by frictionless-py, we can consider integrating them.

• $schema: https://datapackage.org/profiles/2.0/datapackage.json
• contributors: Replace role with roles array populated with DataCite terms (creator, DataCollector, DataCurator, possibly DataManager) and update zenodo.py accordingly.
• dialect: Add type: delimited depending on outcome of Add a dialect.type property frictionlessdata/datapackage#1055
• schema: Add fieldsMatched: exact for datapackage.yaml and fieldsMatched: superset for submission/datapackage.yaml (assuming this latter still results in an error if a required field is missing).
• field
  • Set pipe-delimited fields to type: list and update glenglat.read_data (and downstream code) accordingly.
  • Move constraints.enum to categories, where each category has a value and a description, update glenglat.read_data (and downstream code), and update documentation templates accordingly.