- Update term context section
- Add option to define a default class for declare_reference*
- Use defined symbol identifiers \<quote> and \<doublequote>
to simplify caveat section about lexical conventions
- Rename Manual theories to avoid issues
when using Syntax.parse_term that is not compatible with
with long-names staring with a number or an underscore
- Rewrite names used as mixfix annotation
for the term-antiquotations to rule out
mixform form excluded symbols