### Description
Introducing a new class ORTPipelineModule to handle wrapping layers in
DeepSpeed pipeline parallel.
### Motivation and Context
To support pipeline parallelism on ORTModule.
This PR will include an initial support of deepspeed Pipeline
parallelism.
- [x] Support Pipeline parallel where layers are nn Modules in
Sequential.
- [ ] Support LayerSpec and TiedLayerSpec
- [ ] Enable partitioning to accept List
- [ ] Full-GPU Graph Consolidation
- [ ] Subgraph Merging for Inference
