odd naming convention

It's seems odd that a library named `done-component` is centered around a tag called `can-component`. This results in a bit of confusion at first glance of the relationship between the `can-component` library & the `` tag. A novice to CanJS looking at a codebase would look at the `can-component` docs and see no mention of such a tag.

Obviously the library name `can-component` was already taken, but was there a conscious decision not to make the root tag of a .component file ``?

I propose we add allow .component files to have a root tag of `` while still allowing `` for backwards compatibility. If we did this I'd also suggest updating the docs to use `` in their examples.