Update environment requirements without making a new virtual environment

[mehcode]

First off I want to say 👍 awesome stuff here.

I would appreciate the ability to modify the requirements.txt file and instruct nodeenv to update my "global" requirements without having to destroy and rebuild the environment.

[kylehayes]

I've been using --force for that.

[shellscape]

@kylehayes can you elaborate? I don't see that option documented anywhere.

[kylehayes]

@shellscape, you're going to make me remember that far back :-P
Looking at my notes it looks like I used it like so:
nodeenv --requirement=./requirements.txt --jobs=4 --force env

[ekalinin]

I think that both of these options (--force and --update) can coexist together.