Add test to ensure the Token queue used by the new lexer can be pushed and poped.
Add TokenQueue class and code.
Refactor tests about token queue to be in form of a scenario. This is clearer and better for documentation.
Add doc comments to all the TokenQueue methods (most of them ripped of the std::deque documentation with some minor adaptation).
Add new tests about TokenQueue pop(const TokenType) method... but they all already pass with no problem
Whitespace correction.
Remove redondant NewLexer/TokenQueue tests.
Refactor new lexer test to form a correct scenario.
Add test to ensure the new parser consumme tokens and produce AST.
Add new parser code to process correctly empty token queue.
Refactor test files. Now we have specialized tests files instead of one monolithic (and insanely long) file.