Use a different class library

[sholladay]

Hi and thanks for your great work on this project. 👏

Is there any way you could replace the component-classes dependency with something else? It's causing a lot of headaches for me due to component/classes#31 and their conditional requires. There hasn't been any activity over there for more than two years - it is unmaintained.

On a related note, since those require()s are to support IE, what do you think of dropping IE support and just using classList?