Add version_info tuple (#48414)
Summary:
Add a `version_info` similar to `sys.version_info` for being able to make version tests. Example generated `version.py`:
```
__version__ = '1.8.0a0'
version_info = (1, 8, 0, 'a0')
# or version_info = (1, 8, 0, 'a0', 'deadbeef') if you're in a Git checkout
debug = False
cuda = None
git_version = '671ee71ad4b6f507218d1cad278a8e743780b716'
hip = None
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/48414
Reviewed By: zhangguanheng66
Differential Revision: D25416620
Pulled By: malfet
fbshipit-source-id: 20b561a0c76ac0b16ff92f4bd43f8b724971e444
