tests: Use a static parse context for tests

src: Rename syntax to token

parse: Remove SyntaxType ...

Once again I find myself in the pattern of having a useless 'type' value
that just complicates my life. In this case the correct appproach is to
output the AST directly.

syntax: Refactor draw_syntax_random and add draw_syntax_texttoken ...

I realized draw_syntax_classified is the same as draw_syntax_random, so
just merge them.

Also add draw_syntax_texttoken explicitly meant to weed out cases where
token type is not set.

tests: Clean up syntax and parse code

tests: Refactor getter and setter tests in to a template

parse: Pass a context to the parse function

parse: Use an error context for clear_notes

parse: Allow attaching a ParseContext to a ParseErrorException

parse: Add parse contexts for later error reporting

tests: Fix ParseError exception tests not wroking

tests: parse: Remove unused insert_random

tests: parse: Clean up some includes

tests: parse: Move note tests to their own files

tests: parse: Move text tests to its own file

tests: parse: Move bool tests to its own file

tests: Move parse to its own directory