i18n: Add new module containing a Message class ...

This Message class will be used to format localized text later.

tests: Move parser error tests to its own file

parse: Have parse run parse_file

parse: Add file parser

parse: Add directive parser

tests: Fix draw_wrong_statement_at drawing invalid values

tests: Note what we expect for test_parse_set_valid

tests: Copy tokens in template_test_invalid ...

This makes debugging easier as our input data isn't consumed.

parse: Add conditional statement parser

parse: Add Set node parse code ...

I've taken a different approach this time with my tests by avoiding
decorated functions where I can and adding big upfront documentation
about how things work.

I've deprecated the old decorated functions and hopefully will remove
them during a refactor and cleanup.

parse: Add statement parsing

tests: Document expected parse task

tests: Test parse_value error propagation

parse: Add code for parsing values

tests: parse: Clarify what error_on_token does

tests: parse: Use a mock class for note skipping

tests: Use a static parse context for tests

tests: Use a static token location for random tokens

tests: Use static tokens with static locattions

tests: Use static token location for tokenizer test

tests: Fix test reference invalid name

tests: Fix test_tokenize not testing whitespace ...

This relied on draw_token_random which now doesn't include whitespace

tests: Document parse error exception codes

parse: Reserve keywords for reference names

tests: Move whitespace code to test_tokenize ...

The parser doesn't have to worry about whitespace, so it's not worth
worrying about it here.

parse: Parse a reference node

tests: Add garbled strategy for draw_token_random

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.

parse: Parse text and bools to AST types