Write a real SQL parser

[lintool]

Afterburner takes as input "FluentSQL": many people will just want to write straight-up SQL. We should implement a parser.

Probably makes sense to write a parser that turns plain-old SQL into our fluent representation? That way, we can just think of our fluent representation as an AST.

Whether we can adapt an existing SQL parser in js or write one from scratch... that will depend on some research...