Addressing issue #28.
Addressing issue #28.

A bug in Polygon.holes, was returning a list of vertices.  Should have been returning a list of lists of vertices.

pombreda/pysal,Alwnikrotikz/pysal,AlanZatarain/pysal,tectronics/pysal,AlanZatarain/pysal,Alwnikrotikz/pysal,google-code-export/pysal,tectronics/pysal,google-code-export/pysal,google-code-export/pysal,AlanZatarain/pysal,tectronics/pysal,google-code-export/pysal,Alwnikrotikz/pysal,pombreda/pysal,pombreda/pysal,pombreda/pysal