Using asyncio on jupyter notebook

[Cy-47]

• I have marked all applicable categories:
  • documentation request (i.e. "X is missing from the documentation." If instead I want to ask "how to use X?" I understand StackOverflow#tqdm is more appropriate)
  • new feature request
• I have visited the source website, and in particular
  read the known issues
• I have searched through the issue tracker for duplicates
• I have mentioned version numbers, operating system and
  environment, where applicable:

  import tqdm, sys
  print(tqdm.__version__, sys.version, sys.platform)

Currently, only tqdm.asyncio, which is incompatible with notebook (broken for nested loops), supports gather. For notebooks using tqdm.notebook, it is only possible to iterate through tqdm(asyncio.as_completed(requests)). When the order of the return values is important, this is unusable. Please support gather for tqdm.notebook, thanks! (Also maybe consider letting notebook and terminal tqdm classes have access to the same async functions, e.g. inherit it)