Missing `-khtml` vendor

[niftylettuce]

http://stackoverflow.com/a/2212549

[niftylettuce]

-khtml I believe is the only one, not sure how much this is used.

[kizu]

-khtml- is not needed to be there. Adding it would greatly increase the size of resulting CSS, also, other frameworks tend to remove it from their code. Like Compass did.

And if you need it hardly, you can always redeclare the prefixes and the needed mixins, like this for border-radius:

vendor-prefixes = webkit moz o ms khtml official

border-radius()
  pos = ()
  augmented = false
  for args in arguments
    for arg in args
      if arg is a 'ident'
        append(pos, arg)
        augmented = true
      else
        append(pos, arg)
        if augmented
          -apply-border-radius(pos)
          pos = ()
  vendor('border-radius', pos, only: webkit moz official khtml) unless augmented

And you'll get this vendor prefix. However, it mustn't be there by default, so I think this issue can be closed.