This new table should be used for transient values that don't need to end up
in the loader environment. Generally, these will be things that are internal
details that really aren't needed or interesting outside of the config
module (e.g. if we changed how ${module}_* directives work, they might use
this instead).
To start, populate it with loader_conf_files. Any specific value of
loader_conf_files isn't all that interesting; if we're going to export it,
we should really instead export a loader_conf_files that indicates all of
the configuration files we processed. This will be used to reduce
bookkeeping overhead in a future commit that cleans up readConfFiles.