CDMI 3.0 - Add RFC 8615-based capabilities support

[dslik]

The CDMI 3.0 standard shall add support for RFC 8615 ".well-known" capabilities discovery. (https://datatracker.ietf.org/doc/html/rfc8615)

CDMI 3.0 servers shall provide ".well-known" capabilities.
CDMI 3.0 servers that support CDMI 2.x/1.x clients shall continue to provide "cdmi-capabilities" capabilities.

CDMI 3.0 clients shall use ".well-known" capabilities.

For virtual hosting, we need to specify how ".well-known" is handled. This can go into the section discussing CDMI exports.

Next step is to create an updated version of the capabilities section of the CDMI specification, which can be published on this repository and sent to IETF for review.