This tool does the simple job of checking a Prometheus rule file for validity
and printing the parsed rules if the loading succeeds. This came out of
an immediate need to quickly verify changes to existing rule files.
This very simple tool dumps all samples in a LevelDB metrics storage
together with their chunk information. This is very crude for now - I
just whipped it up because I needed to debug something. We should add
printf-style formatting support for it in the future to indicate what
information to output for each sample in the database. We could also
support inspecting the index databases.