Update exported metrics to spit the number of bad IPs per jail using metric
value labels. This includes a change to the database code to use a
different query that groups the count by the `jail` column.
Add dependencies on `sqlite` to allow connecting to the fail2ban database.
Add a new `db` module to handle all the database connections and data
queries used to generate metrics.
Export a new metric for the total number of bad IPs stored in the fail2ban
database.
Add dependency on the prometheus library to start exporting metrics. Add
a new `up` metric that always returns `1` to ensure the exporter is
working as expected.
