Merge pull request openvpi#49 from openvpi/augmentation

Support data augmentation and gender control

Fix crash when running multiple rolls with speaker mix

Merge branch 'refactor' of https://github.com/openvpi/DiffSinger into…

… refactor

Fix a bug causing cpu inference unavailable

optimize code

Merge branch 'refactor' of https://github.com/openvpi/DiffSinger into…

… refactor