Updated container to run exec commands.

I am writing an app that uses exec to get the current env variables. I have added and successfully used this in my project (which i will be publishing soon to docker)

exec has 2 api commands, therefore i created the 2 functions, and in the example i created you can see the usage.

Please let me know if this is the proper design for the app and if not what needs updating.
These are not accordingly documentation. 201 – no error, 404 – no such exec instance