Mapbox-vector-tile

- python3 updates
- enforce winding order on multipolygons
- update key/val handling
- round floating point values instead of truncating
- add option to quantize bounds
- add option to flip y coord system
- add ability to pass custom extents

- Add compatibility with python 3
- Handle multipolygons as single features
- Use winding order from mapbox vector tile 2.0 spec
- Support custom extents when decoding

- Decode string keys to utf-8

- Allow encoder to accept shapely objects directly

- Handle tiles from java-vector-tile (zero pad binary integers)
- Update README

- Handle unicode properties