Improve references to WS-Calendar for clarity, terminology, and adaptation of inheritance

Rewrite and review the ws-calendar narrative for clarity and precision, including Stop sentence after "inherited" and add discussion of inheritance earlier in document. Use WS-Calendar Gluon in first reference in each section. Add conformance section on inheritance to last section. Terminology needs to be consistent; e.g., a Gluon acts as a handle to a Sequence Capitalize Interval, Gluon, Sequence throughout as defined terms.