Deprecate legacy datatypes

[aj-stein-nist]

User Story:

As a Metschema developer, in order to reduce implementation surface and complexity, I would like to explicitly deprecate the older, legacy data type names from camelCase to complete migration to kebab-case, remove the legacy, and document its deprecation before upcoming major release (1.0.0).

Goals:

• [x] Remove old data types from Metaschema module
• [ ] Add deprecation constraint to Metaschema module
• [x] Remove old data types from Metaschema XML Schema? #561
• [ ] Remove old data types from Metaschema JSON Schema?
• [x] Review documentation and remove any reference in specs and examples to legacy name style #562
• [ ] Review all example models in repo and deployed to website to confirm deprecated model datatypes no longer used
• [x] Add final note on data types page in a warning box and indicate the legacy style is no longer supported https://github.com/usnistgov/metaschema/pull/560

Dependencies:

N/A

Acceptance Criteria

• [ ] All website and readme documentation affected by the changes in this issue have been updated. Changes to the website can be made in the docs/content directory of your branch.
• [ ] A Pull Request (PR) is submitted that fully addresses the goals of this User Story. This issue is referenced in the PR.
• [ ] The CI-CD build process runs without any reported errors on the PR. This can be confirmed by reviewing that all checks have passed in the PR.

{The items above are general acceptance criteria for all User Stories. Please describe anything else that must be completed for this issue to be considered resolved.}

[aj-stein-nist]

Can I get a spotcheck of the intent here, @david-waltermire?

1. Regarding the metaschema-module-metaschema, they are already gone and there are no deprecation warnings. With M1-M3 milestones, we are still technically not "1.0.0 ready" yet, so do you want to add deprecation constraints t @level="WARNING" or just leave it out and consider it done?
2. Regaring datatypes defined in XML Schema, we have both but no deprecation strategy. Just remove them?
3. The JSON inventory is complicated because it really doesn't mention any names for datatypes and looks just to be a self-contained JSON Schema. Thoughts?