Draftjs-exporter

Last release before switching to BeautifulSoup4 / html5lib. If we ever need to switch back to lxml, it should be as simple as looking at the code at [v0.3.3](https://github.com/springload/draftjs_exporter/tree/v0.3.3).

Added

- Add wrapper method to create new elements.
- Add wrapper method to retrieve an element's list of classes.

Fixed

- Fix exporter crashing on empty blocks (renders empty string instead)

Fixed

- Use HTML parser instead of XML for DOM API

Added

- Automatic conversion of entity data to HTML attributes (int & boolean to string, `class` to `class`).
- Default, extensible block & inline style maps for common HTML elements.
- React-like API to create custom entity decorators.
- DOM API to abstract HTML building code.
- Dynamically generate test cases from JSON fixture
- Raise exception for undefined entity decorators

Changed

- (Breaking change) Exporter API changed to be closer to React's
- (Breaking change) Entity decorator API changed to be closer to React's

Fixed

- Nested blocks backtracking creating multiple wrappers at the same depths instead of reusing existing ones ([9](https://github.com/springload/draftjs_exporter/issues/9))

Removed

- Removed Token entity (identical as Null)

Added

- Support for `<hr/>` tag / `TOKEN` entities
- Support for wrapped item nesting (arbitrary depth)

First usable release! 🎉