Fix #12: Add the lowercase geometry type handling

Add a workaround to no holes polygons, To be verified
Fix #12, #15: Add the lowercase geometry type handling and workaround to handle polygons without holes
Merge branch 'bug/12' of github.com:filosganga/geogson into bug/12
Merge pull request #14 from filosganga/bug/12

Fix #12: Add the lowercase geometry type handling
Fix #15: Add the polygons without holes support