- Cosmetic: replace tabs with blanks, strip trailing white space,
and update copyright headers with spec-cleaner.

- Update primitive to version 0.6.4.0.
## Changes in version 0.6.4.0
* Introduce `Data.Primitive.PrimArray`, which offers types and function
for dealing with a `ByteArray` tagged with a phantom type variable for
tracking the element type.
* Implement `isByteArrayPinned` and `isMutableByteArrayPinned`.
* Add `Eq1`, `Ord1`, `Show1`, and `Read1` instances for `Array` and
`SmallArray`.
* Improve the test suite. This includes having property tests for
typeclasses from `base` such as `Eq`, `Ord`, `Functor`, `Applicative`,
`Monad`, `IsList`, `Monoid`, `Foldable`, and `Traversable`.
* Fix the broken `IsList` instance for `ByteArray`. The old definition
would allocate a byte array of the correct size and then leave the
memory unitialized instead of writing the list elements to it.
* Fix the broken `Functor` instance for `Array`. The old definition
would allocate an array of the correct size with thunks for erroring
installed at every index. It failed to replace these thunks with
the result of the function applied to the elements of the argument array.
* Fix the broken `Applicative` instances of `Array` and `SmallArray`.
The old implementation of `<*>` for `Array` failed to initialize
some elements but correctly initialized others in the resulting
`Array`. It is unclear what the old behavior of `<*>` was for
`SmallArray`, but it was incorrect.
* Fix the broken `Monad` instances for `Array` and `SmallArray`.
* Fix the implementation of `foldl1` in the `Foldable` instances for
`Array` and `SmallArray`. In both cases, the old implementation
simply returned the first element of the array and made no use of