[NEW FEATURE]Global bookkeeping stragegy

[lbaumo]

We need to generalize the bookkeeping stragegy across modules. Even switching from megapipe to theli images has been extremely disruptive to the pipeline. The current implementation is very inflexible, with many things hardcoded. Given a list of files, we need a starndard method that can separate out the exposure number, directory, file pattern, ccd number, and file extension, and we need to use it for every single module.