Formal specification of 0.5.x language

[evinism]

As mentioned in the development README, the 0.4.x language forms the first standard of the language.

This requires:

1. Formalizing the MistQL grammar
2. Developing a language-independent test suite for language compliance.
3. [more as I think of it]

[evinism]

Language independent test suite initialized in #53. Still needs to be filled out. Most tests in JS world should be made into language independent tests.

[evinism]

Changing to 0.5.x because there are some important things that need to be fixed up beforehand.

[evinism]

Still on track for 0.5.x language standardization. With multiple implementations, we're coming awfully close to having reasonable behavior.

[evinism]

The only missing piece for standardization seems to be #76