failing unit test for loading a WKT multipolygon with holes

Hi !

The library fails to load multipolygons with holes correctly.
Inner rings of polygons are loaded as outer rings of polygons :
```MULTIPOLYGON(((10 10,10 20,20 20,20 15,10 10),(12 12,12 18,18 18,18 17,12 12)),((60 60,70 70,80 60,60 60)))```
is loaded as
```MULTIPOLYGON(((10 10,10 20,20 20,20 15,10 10)),((12 12,12 18,18 18,18 17,12 12)),((60 60,70 70,80 60,60 60)))```

I'll have a look in the source to see if I can spot the bug, but I'm sure it will be easier for you !

Thanks for the library !

PS: why don't you activate the issue tracker ?