Use `primitive` instead of duplicating primop wrappers.

[oberblastmeister]

There are a lot of primop wrappers in Data.ByteString.Short.Internal that are already in primitive. Can we use primitive instead of duplicating this code? I think it would also be useful if type ShortByteString = ByteArray.

[sjakobi]

bytestring can't depend on primitive as long as primitive isn't a GHC boot library.

[clyring]

The duplication is a bit unfortunate but isn't causing any real pain. I would have no particular objection to primitive becoming a boot library so that bytestring and other boot libraries can depend on it, but unless that happens I don't think there is anything actionable here. I don't think this issue tracker is a good venue for further discussion on this topic; perhaps try asking around at the ghc-devs or libraries mailing lists if you wish to discuss this further.

(Regarding your type ShortByteString = ByteArray suggestion: I don't think this will ever happen; their instances do not agree perfectly. But a newtype wrapper is still up for discussion: see #410.)

[Bodigrim]

Given the amount of pain which being a boot library imposes, I would rather keep their list as short as possible.

That said, I intend to make progress with #410 before bytestring-0.12. Cf. haskell/text#474 and haskell/primitive#354.