Faster TaskDataset, new vision datasets & examples

v0.1.0

Added

• A CHANGELOG.md file.
• New vision datasets: FC100, tiered-Imagenet, FGVCAircraft, VGGFlowers102.
• New vision examples: Reptile & ANIL.
• Extensive benchmarks of all vision examples.

Changed

• Re-wrote TaskDataset and task transforms in Cython, for a 20x speed-up.
• Travis testing with different versions of Python (3.6, 3.7), torch (1.1, 1.2, 1.3, 1.4), and torchvision (0.3, 0.4, 0.5).
• New Material doc theme with links to changelog and examples.

Fixed

• Support for RandomClassRotation with newer versions of torchvision.
• Various minor fixes in the examples.
• Add Dropbox download if GDrive fails for FC100.