[Task] Add support for saving chrome trace files to s3 urls and Azure blob

[chauhang]

Add support for saving the generated chrome trace files to s3 URLs. This works for Tensorboard SummaryWriter but is not supported for the Profiler traces.

Current Behavior
on_trace_ready=torch.profiler.tensorboard_trace_handler('s3://tb-demo/pytorch/')

Creates local files like:

(base) ubuntu@ip-172-31-22-142:~$ ls 
s3\:/tb-demo/pytorch/ip-172-31-22-142_14545.1618682202565.pt.trace.json 
s3:/tb-demo/pytorch/ip-172-31-22-142_14545.1618682202565.pt.trace.json

Expected Behavior
The chrome trace files should be saved in the S3 bucket

[guotuofeng]

#182

[guotuofeng]

Add documentation work item: #196