Allow setting environment variable automatically for jobs

This is low priority at the moment, please vote up if you will find it useful.

Control of env variables for launched jobs. This could be based on a special node in the job config:

env:
  OMP_NUM_THREADS: 1 
  # copy env from running machine
  USER: ${env:USER} 

TO BE CLEAR: You can already use environment variables in configs: See the OmegaConf documentation.

This issue is about allowing easier control of the environment variable of Hydra apps for other purposes (for example, setting OMP_NUM_THREADS automatically to 1).

[omry]

It was not clear from the issue description, I updated it. I recommend everyone here spend the time to read the OmegaConf documentation. there are many good features there you should know about if you use Hydra.

[omry]

1. This is a feature request to support automatically SETTING the environment variables for Hydra jobs.
2. You can already USE environment variables in the config (see my edit to the task description).
3. I am planning to add this functionality for the next Hydra version.
4. This is marked as “good first issue”, meaning it’s not hard to implement.

If this is so important to people, they can step up and help.