Before going public:

* finish outstanding todos, unimplementeds and missing types in code
* Dictionary::suggest(&self, word: &str) -> Vec<String>
* rewrite checker to use Iterators rather than returning Vecs where possible
	* this change for break_words was a very noticeable performance boost
* expand unit tests

After going public:

* experiment with smartstring
* experiment with ahash / other Hashers
* experiment with not compiling AffixPattern
    * Nuspell scans the pattern string on-the-fly and we could too
* integration tests against a real dictionary
