merge multiple profile context together

[matthewygf]

Use cases:

• i have multiple training (2) running on the same GPUs and i want to profile each process, but want to see them at the same time on the profiler-ui.

current profiler ui takes --profile_context_path=path/to/directory/profile

is it possible to do multiple visualization like tensorboard? --profile_context_path=path/to/directory

[ChrisAntaki]

Hey Matthew, this is an awesome idea! I added it to a new feature requests section on the README