Documentation of environment variables

[anjohnson]

A colleague has just pointed out that the only place where the PVA environment variables such as EPICS_PVA_ADDR_LIST are documented is in an Excel spreadsheet on the old website. A git grep EPICS_PVA_ADDR_LIST on this repo only turns up .cpp files and I just grepped through my local copy of the old website and found nothing else there.

[mdavidsaver]

Yup.

While not an immediate a substitute, the PVXS documentation of client and server configuration covers the EPICS_PVA* environment variables.