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Fetch benchmarks results on all nodes, will rsync after each benchmark.
The results directory structure on control node is as follows:

```
outputs/
└── datetime
    ├── nodes
    │   └── node-0
    │       ├── benchmarks
    │       │   ├── benchmark-0
    │       │   │   ├── rank-0
    │       │   │   │   └── results.json
    │       └── sb-exec.log
    ├── sb-run.log
    └── sb.config.yaml
```

* Support custom output directory.
* Update document.

__Major Revision__

* Support lazy import.
* Not importing benchmarks when running `help`, `version`, `deploy` commands, etc.

Update logger class.
* add file handler along with stream handler
* add colored formatter

Use omegaconf to replace hydra for configuration system:
* remove hydra
* use omegaconf to merge configurations

- Add CLI commands
  * sb version
  * sb deploy
  * sb exec
  * sb run
- Add interface with executor and runner
- Add cli test cases

* benchmarks init.
Co-authored-by: Guoshuai Zhao <guzhao@microsoft.com>