makes stuansready catch empty drawing in conditional

[nick-chura]

I noticed that stuansready was returning true for drawing parts submitted blank in conditional problems. Of course, feel free to deny/close this if there's a better way to fix it.

[drlippman]

Your approach here is fine, but since ';;;;;;;;' would be a really unlikely answer to any other question, I think I'm going to just add a check for that, even if $anstypes isn't provided. That might help some existing questions without needing changes.