Added support for:
- Bidirectional and Layer Parallelism (GEMS+LP)
- Bidirectional and Pipeline Parallelism (GEMS+PP)
- Spatial, Bidirectional and Layer Parallelism (SP+GEMS+LP)
- Spatial, Bidirectional and Pipeline Parallelism (SP+GEMS+PP)
- Support for AmoebaNet and ResNet models
- Support for different image sizes and custom datasets