Lots of work on Parser, including hash and call parsing.

  - Isolate specific operators for precedence.
  - Allow blocks to be top-level expressions (for easy creation of procs
    and lambdas)
  - Stop relying on WHITE? magic token, and be explicit about tokens we
    care about.
  - Isolate commonly used seperators (like " , ") into reusable
    productions.
  - Explicitly disable lookahead on the parser, since it causes problems
    for me.