v0.8.16

What's Changed

• refactorize model classes, handle invalid polygons, minor improvements by @fcakyon in #311
• refactor tests and coco utils by @fcakyon in #313
• fix nms postprocess by @fcakyon in #314
• update predict verbose by @fcakyon in #317
• print exports dirs after process finishes by @fcakyon in #318

Full Changelog: 0.8.15...0.8.16