Beta release

Did some designing, and the interface shouldn't have anymore code-breaking changes. Names more or less settled (for real this time). Only get_jamo_class is still in consideration of change, due to the string return value. In that vein, hcj_to_jamo may get looser parameters in the future, perhaps accepting hangul class inputs.

Korean docs aren't really out yet, but 0.4.1 should put those out. 0.4.1 should also add some extra Unicode blocks.