Builds list and .len files -- get into CVMFS, update on the regular, pull down to servers?

Moved over from here. This is a reminder ticket to either do something stable to keep this updated or close it out of done (and if done, please share how -- usegalaxy.org is outdated again).

https://github.com/galaxyproject/galaxy/issues/981

Start by reading the linked Galaxy issue 981 and checking how the builds list and .len files are currently stored or updated in this repository. Determine whether a stable update path to CVMFS and Galaxy servers is defined; done means either documenting and implementing that path or closing the reminder with instructions for keeping usegalaxy.org current.

Written by the indexing model from the issue text.