2.2.0

Mostly a bugfix release, many bugs/misalignments have been found by running jQuery's test suite (#193) and fixed.

There are some new feature too:

• $.fn.css now supports CSS variables too
• All data attributes can be retrieved at once via $foo.data ()
• Added $.hasData
• $.fn.before|after|prepend|append now support multiple arguments, and the elements are inserted in the proper order
• Attributes can be removed via $foo.attr ( 'my-attr', null ) (passing null as the value basically)