Enabled gather and scatter for bool tensor (#21924)
Summary:
- moving stuff around in order to enable bool.
- Added implementation of atomicAdd(bool, bool)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/21924
Differential Revision: D15883711
Pulled By: izdeby
fbshipit-source-id: 733f35c2bc3d87cec9f9687d72b62d2d2cd7c03e
