fixes for using tablePrefix in tables and the index

[ellis]

This patch makes sure that tablePrefix is properly used.

I actually only changed two lines, but I see that my editor removed trailing spaces too - I hope that's not too confusing.

[ncthbrt]

Thanks for this fix @ellis.
We're not using prefixes, so it has not really been battletested.

[coveralls]

Coverage decreased (-1.9%) to 98.113% when pulling e1b6bbe on ellis:master into ee2586c on ncthbrt:master.