Added

• Add atomic.Float32 type for atomic operations on float32.
• Add CompareAndSwap and Swap methods to atomic.String, atomic.Error,
  and atomic.Value.
• Add generic atomic.Pointer[T] type for atomic operations on pointers of any
  type. This is present only for Go 1.18 or higher, and is a drop-in for
  replacement for the standard library's sync/atomic.Pointer type.

Changed

• Deprecate CAS methods on all types in favor of corresponding
  CompareAndSwap methods.

Thanks to @eNV25 and @icpd for their contributions to this release.