Quest portal can cover down stairs in Trollshaws!

[Taxorgian]

I accepted a warrior quest which failed miserably but the really nasty thing is that the portal was generated where, apparently, the stairs down were. So it overwrites the down stairs and my poor berserker can't even get the troll's ugly stick. I don't know what DG might need to check this but I have saved the stdout file.

[darkgod]

FIxed in beta11 (I think)