refresh css in browser (dev mode) without having to reload the page

[alexandred]

Just a simple addition to allow for immediate CSS refreshing (through cache invalidation) without having to reload the page.

[ryanstout]

@alexandred have you had any time for this issue. I'm still thinking we can make it work, but we'll need to track the requires. Thanks!

[alexandred]

@ryanstout I put it on hold after you said you preferred we wait until you've sorted multiple root components. I think I've got require tracking all organised in my head (some of the code is already sorted), its just a matter of polishing it off. I can sort that out soon if you'd like.

[ryanstout]

@alexandred sorry, had forgotten I had said that. It might be a little while before I get to the multiple root components. I think it probably makes since to merge in if you have the require edge cases worked out. Then when I add multiple root components, we can change it. Thanks!