v0.4.0

Refactor and lots of bug fixes

The biggest user-facing changes are these:

• Default style changed to wikipedia
• Add titlecase-sentence function
• Add user option titlecase-command that can be a function, a string, or a list of strings.

What's Changed

• Fix bug with phrasal verbs (downcase ran on nil) by @ideasman42 in #20
• Add tests that use generated data by @ideasman42 in #21
• Correct spelling, use punctuation. by @ideasman42 in #22

Full Changelog: 0.3.0...0.4.0