This ticket implements a set of tooling in documenteer that allows us to rendering installation documentation in pipelines.lsst.io that is exactly appropriate for the EUPS tag of the stack being documented. Some examples of functionality are:

• Include the right EUPS tag in the eups distrib install documentation line.
• Reference the right Python/Conda dependency files for the EUPS tag
• Populate the version labels throughout the documentation.

Inside the stack documentation build container we can use the EUPS_TAG environment variable. (https://github.com/lsst-sqre/jenkins-dm-jobs/blob/master/pipelines/lib/util.groovy#L1155)

An alternative would be to use the EUPS APIs to figure out what tag is currently installed (this might be useful for local builds by developers, but in that case perhaps it would be better have some sort of default fallback).