[m-rev.] for review: improve error messages for invalid determinism categories

[Zoltan Somogyi]

On Wed, 22 Jun 2016 15:56:12 +1000 (AEST), Julien Fischer <jfischer at opturion.com> wrote:
> For review by anyone.

Please commit it. I will have a look at it then.

Zoltan.