backfill process for old debug.log files

[josibake]

it would be really handy to be able to run old log files through bmon for stuff where historical data is needed (think old mempool logs). at the very least, these can be scripts and not apart of the actual bmon infra, but i think it makes sense to have them in this repo, at the very least. its also a good way to test bmons log parsing over different versions of core.

a few considerations:

• if we can just load a log file and have bmon parse it, it might be good to separate it into its own queue so it doesnt affect the live data collection
• it might also make sense to have a bmon-cli which allows us to access log parsers and write our custom logic of where to put the data (either in the postgres database or some offline storage like GCP), but this way we ensure that all of the logic to parse the data is consistent across time