Numerous fixes to code broken by API changes since last release
Inner rings (holes) are saved as separate polygons in Geometry Export
Metadata.txt minimum version now has to be 2.0.0 to be fetched from repository,
even though Master is 1.9
QgsFeature::attributes() no longer QVariant (API change?); QVariant toString(),
toDouble() and toInt() replaced by unicode(), float() and int()
Coded substitute for removed QgsVectorLayer::featureAtId()
Conditional call to isUsingRendererV2() - old renderer V1 has been removed
