Updated README with halcyon-kubernetes venv

[retr0h]

Added the steps necessary to build and enable the virtualenv provided by halcyon-kubernetes.

This change is 

[alanmeadows]

@retr0h Thank you for your submission, sir.

[retr0h]

@retr0h Thank you for your submission, sir.

Hey Alan, long time no talk 🎸

[nadeemanwar]

@retr0h When I try to run it, I see this error. New python executable in /home/jenkins/workspace/halcyon-vagrant-kubernetes-virenv-build/halcyon-kubernetes/venv/bin/python

18:08:43 Installing pip, wheel...done. 18:08:44 . venv/bin/activate; pip install -r requirements.txt

18:08:45 Collecting ansible==2.2.1 (from -r requirements.txt (line 1)) 18:08:45 Using cached ansible-2.2.1.0.tar.gz

18:08:46 Could not import setuptools which is required to install from a source distribution. 18:08:46 Please install setuptools. 18:08:46 Makefile:4: recipe for target 'venv/bin/activate' failed 18:08:46 make: *** [venv/bin/activate] Error 1

[retr0h]

@aric49 Let me know how you would like me to proceed. Unfortunately, one cannot perform this work in another script. When doing this in a script, the source occurs inside the scripts shell, which loses the environment once the shell exits.

Maybe this change is unnecessarily complicating things. However, this repo cannot leverage the changes recently merged into halcyon-kubernetes.

[retr0h]

@nadeemanwar Does this discussion fix your problem? https://github.com/att-comdev/halcyon-kubernetes/pull/46

[aric49]

@retr0h --- That's fine if we can't leverage a sub shell to setup the virtual env. I just wen through your most recent changes and followed them straight through the README.md and it worked on my workstation.

LGTM

@v1k0d3n -- Any concerns with merging?

[v1k0d3n]

@aric49 nope. go ahead and merge. i tested them and they worked on my workstation as well.

[retr0h]

@aric49 all good with this?