v1.3.0

Changes:

• Added option for vessel segmentation (hepatic vascular system)
• Added pretrained deep vessel model
• Added Chainer and CuPy as dependencies, to support new model
• Added both CPU and GPU support for new model
• Fixed such that two models can be run sequentially, without GPU memory leakage
• Major refactoring

Full Changelog: v1.2.0...v1.3.0