Big release this time, with some major improvements, and some important breaking changes as well.

Breaking changes:

Removed special types for classattribute handling inside dict attributes. An alternative is now to use the new "Object attributes"
Removed keyword attributes complex syntax to emulate non standard HTML attributes. You can still generate those with Dict attributes or the new "Object attributes"
Renamed the former markupy.tag module to markupy.elements, to be more in line with the internal semantics and with the new markupy.attributes module as well

New features:

Major rework of internals to simplify the structure, optimize performance and reliability with type and runtime checks
Reorganize the docs to make them easier to grasp for both beginners and advanced users. And we now have a logo!
Introduction of "Object attributes", including suggestion and auto-completion for HTML5 attributes and helper utilities for some attributes, including the attr.class_() which can take as an argument a string, a dict or a list of classes.