add_class, remove_class & has_class depracated

the functions add_class, remove_class & has_class have been depracated
in favour of the corresponding jquery alternatives. There isn't too much
of a performance or elegance bump associated with it to choose these
implementations over the jquery ones.
Increased the functionality of create_element

Previously create_element would generate an element based on a developer
inputted tag name and option text. Now it takes in tag name, however
instead of text it can take in a whole node, and can also take in an ID
and a list of classes to assign to the newly generated node.