* Fixed string parsing and escaping
* Unicode now consistently used internally
* New method `dumpu` added that returns unicode
* `dumps` method now takes optional encoding arguments: `output_encoding`
(specifies encoding of output string) and `string_encoding` (specifies
encoding of non-unicode strings in object to be serialized), both default to
`'utf-8'`
* `loads` now takes optional argument `input_encoding`, defaults to `'utf-8'`
* New method `loadu` added that assumes unicode input
* Bump dependencies