libpromises/evalfunction.c: let mergedata() use VarRefValueToJson
cf-agent/verify_packages.c: Improve logging
Redmine#4847: limit peerleader() range to 2-64 as per docs
Redmine#5289: add warning when a Mustache section gets a non-iterable
Merge pull request #1600 from tzz/redmine5289-mustache-warning-non-iterable

Redmine#5289: add warning when a Mustache section gets a non-iterable
Merge pull request #1587 from tzz/refactor/mergedata/VarRefValueToJson

libpromises/evalfunction.c: let mergedata() use VarRefValueToJson
10_files/templating/mustache_section.cf: simplify with dcs_passif_output1