+When check_whitelist is set, only images from URLs matching a regex in the
+domain_whitelist array are accepted for local storage. When check_blacklist
+is set, images from URLs matching any regex in the domain_blacklist are
+denied local storage. When both lists are checked, only images from URLs
+that match a regex in the domain_whitelist and that match no regexen in the
+domain_blacklist are accepted for local storage.
+