Finalize the Ion 1.1 specification

[toddjonker]

Here are some thing that I think are (some) requirements for "finalizing" the spec.

• Merge the denotational semantics document from its home at https://github.com/toddjonker/ion-docs/commits/main/ into the ion-11-specification branch with the narrative spec doc.
• Finish the denotational semantic model, so we have a formal spec and reference implementation for the dynamic behavior.
  • We should reach consensus on what it would take to make the semantic model the normative standard. That is, treat it as the primary specification such that the old prose documents (particularly the symbols page) are supplemental explanations.
• Merge the latter branch into the gh-pages branch
  • Automate building the PDFs and making them available for viewing online.
• Personally, I think the spec shouldn't be considered finished without a fairly complete suite of conformance tests.

This list is not strongly-ordered and is not a complete list of requirements. For example, the narrative doc still needs a fair amount of editing for consistency/correctness and has some notable gaps.