DeepSpeed

da84e60d - add missing license info to top of all source code (#2889)

add missing license info to top of all source code (#2889) Co-authored-by: Michael Wyatt <michaelwyatt@microsoft.com> Co-authored-by: Conglong Li <conglong.li@gmail.com> Co-authored-by: Olatunji Ruwase <olruwase@microsoft.com>