* move std.atomic.Atomic to std.atomic.Value
* fix incorrect argument order passed to testing.expectEqual
* make the functions be a thin wrapper over the atomic builtins and
  stick to the naming conventions.
* remove pointless functions loadUnchecked and storeUnchecked. Instead,
  name the field `raw` instead of `value` (which is redundant with the
  type name).
* simplify the tests by not passing every possible combination. Many
  cases were iterating over every possible combinations but then not
  even using the for loop element value!
* remove the redundant compile errors which are already implemented by
  the language itself.
* remove dead x86 inline assembly. this should be implemented in the
  language if at all.