Clean up elixir keywords a bit, add more features

Adds support for:

- defrecord
- alias
- use
- fn

Also made Elixir test output include more of these usages to catch bugs.
Finally, reduced ruby keyword count from elixir keywords to help with
some scoring boundary issues that would likely have come up otherwise
(they were scoring the blocks of ruby an elixir as only one point
different with the previous commit - now they are more substantial)