Please describe the problem:
Reports that try to access tax table details via (gncTaxTableGetEntries) get a pointer that shows up as "#<swig-pointer PriceList * ...>" instead of a list of GncTaxTableEntry objects.

Steps to reproduce:
1. Download my test report from http://www.fbcs.co.uk/files/gnucash/taxtablebug.scm
2. Install it in the usual way by making an entry in .gnucash/config.user
3. Run the report for an invoice that uses a taxtable.


Actual results:
The report includes:
  ttentries: #<swig-pointer PriceList * 9a11c10>
  That looks like a PriceList instead of a TTEntry!

Expected results:
The report should include:
  ttentries: (#<swig-pointer GncTaxTableEntry * 94a0f00>)
  That seems to be a proper TTEntry


Does this happen every time?
Yes

Other information:
My patch is available at http://www.fbcs.co.uk/files/gnucash/taxtable.patch.txt