Deprecate/remove default tags.

[back2dos]

Default tags are used to bring <div /> and such into scope. They complicate tag resolution a lot (which in turns makes supporting IDE services all the harder) and they really just save the user one * import (which can go into import.hx).

I'm inclined to remove them straight away, in favor of a clear error message - unfortunately, the user will get to see it in builds, but not in diagnostics, but I suppose most hxx (i.e. coconut) users are pretty used to IDE services being weird.

[kLabz]

Will that impact react-next? If so, any idea what I should be doing to be compatible?

[back2dos]

Nope, react-next uses its own generator, which simply put knows what a div is. It will be unaffected.

[back2dos]

Well, after removing them and trying to migrate a bigger project I've realized this is a pita. Should deprecate instead.