* Docs coming together
* Adding PTB3 tokenizer back in, so can understand how much boilerplate is in the docs for multiple tokenizers
* More docs
* Add tests for word shape
* Add orth features
* Begin testing more functionality
* Pass tests. Need to implement more feature functions.
* Add canon_case function
* Switch canon_case to get value, to avoid keyerror
* Add asciify string transform, and other bits.
* Add incomplete tests of asciify function
* Add tests for word shape features
* Add tests for canon_case
* Add tests for flag features
* Add tests for non_sparse string transform
* Bug fixes to flag features
* Work on tests for flag features
* Fix setup script
* Tweak overview docs
* Refactoring to use Tokens object