`use` and `import` in a class or record definition results in a syntax error

[e-kayrakli]

We can use or import modules in function scope. Trying to do that in a class or record scope, I am getting a syntax error. I think we should be able to do that but that's not a strong preference for me, at all. However, emitting a syntax error for attempting to do so feels wrong and we should provide a more helpful error message.

record R {
  use IO;
}

You can swap record with class, and use with import. The behavior is the same.

[bradcray]

This seems useful to me as well, as a way of making an external module's symbols available to all the primary methods on a record/class, or to use its symbols to define the fields. At least, I can't think of a reason we wouldn't / shouldn't support it.