v0.8.5.7

This release mainly implements a new feature: support for fetching ip lists for matching countries from ARIN - American Registry for Internet Numbers (in addition to fetching from RIPE).

Fairly significant changes have been made to the *fetch and check-ip-in-ripe.sh scripts to allow for automatic selection of the matching registry and parsing its format.
This solves an issue where fetching ip lists for some countries (particularly for US) would usually succeed only on 3rd attempt when fetching them from RIPE.

Users can continue to use the scripts as before, since matching the country to the registry is done automatically.

Also renamed check_ip_in_ripe.sh to check-ip-in-registry.sh and validate_cron_schedule.sh to validate-cron-schedule.sh.

Full Changelog: v0.8.5.6...v0.8.5.7