Create expanded list of capabilities

Following from meltano#2829 (closed) (Gold/Silver/Bronze evaluation framework), we should expand the enumerated list of capabilities.

Today's list:

As of today, Meltano has enumerated the following capabilities:

• Taps:
  • catalog (implies selection capabilities)
  • properties (older version of catalog)
  • discover (ability to create catalog)
  • state (ability to perform incremental replication)

New additions:

The first text in the list is the proposed canonical capability text. (Please feel free to propose updates in comments.)

• Taps:
  • activate-version (#18 (closed))
  • about (--about --format=json)
  • batch (#9 (closed)) (when supported, details are provided in --about)
  • stream-maps (inline transformation/mapper functions)
  • DB-Type Taps:
    • log-based (may be detectable from generated catalog)
• Targets:
  • batch (#9 (closed)) (when supported, details are provided in --about)
  • activate-version (#18 (closed))
  • soft-delete (requires a tap stream supporting activate-version and/or log-based)
  • hard-delete (requires a tap stream supporting activate-version and/or log-based)
  • stream-maps (inline transformation/mapper functions)
  • DB-Type Targets:
    • target-schema (allows overriding of target DB schema)