Add package version constraints to the various dependency lists

[eecavanna]

One list is in content/home/requirements.txt, another list is in a Dockerfile (see below), etc.

docs/pullers/workflow_docs/Dockerfile

Lines 21 to 25 in 4999094

	RUN python -m pip install \
	sphinx \
	sphinx_rtd_theme \
	pillow \
	sphinxcontrib-googleanalytics==0.4

The task here is to include version information so that builds are more "reproducible."