Remove test of export
Remove test of export

Kasim execution on generated models is already tested in the other tests
that call run_kasim. pysb.export functionality, if it is to be tested,
should be done separately for all formats.

johnbachman/pysb,LoLab-VU/pysb,alubbock/pysb,johnbachman/pysb,LoLab-VU/pysb,pysb/pysb,jmuhlich/pysb