(maint) update documentation for PDB-489
Merge pull request #1118 from wkalt/maint/producer-timestamp-documentation-fixes

(maint) update documentation for PDB-489
add db fallback test
fix config 2xdb
change 00 for multiple dbs
remove .vm from 2xdb hostnames
try to fix 30_generate..
be idempotent!
add ruby dev to debian
add second ruby dev
fix 60_
fix remaing presuite tests
syntax
fix 90