Technically `IGNORE_NAME` is a promise that DNSControl will not add, change, or delete records at a given label. This permits another entity to "own" that label.
`IGNORE_NAME` is generally used in very specific situations:
* Some records are managed by some other system and DNSControl is only used to manage some records and/or keep them updated. For example a DNS record that is managed by Kubernetes External DNS, but DNSControl is used to manage the rest of the zone. In this case we don't want DNSControl to try to delete the externally managed record.
* To work-around a pseudo record type that is not supported by DNSControl. For example some providers have a fake DNS record type called "URL" which creates a redirect. DNSControl normally deletes these records because it doesn't understand them. `IGNORE_NAME` will leave those records alone.
*`IGNORE_NAME("*.foo")` will ignore all records in the style of `bar.foo`, but will not ignore records using a double
subdomain, such as `foo.bar.foo`.
*`IGNORE_NAME("**.foo")` will ignore all subdomains of `foo`, including double subdomains.
*`IGNORE_NAME("?oo")` will ignore all records of three symbols ending in `oo`, for example `foo` and `zoo`. It will
not match `.`
*`IGNORE_NAME("[abc]oo")` will ignore records `aoo`, `boo` and `coo`. `IGNORE_NAME("[a-c]oo")` is equivalent.
*`IGNORE_NAME("[!abc]oo")` will ignore all three symbol records ending in `oo`, except for `aoo`, `boo`, `coo`. `IGNORE_NAME("[!a-c]oo")` is equivalent.
*`IGNORE_NAME("{bar,[fz]oo}")` will ignore `bar`, `foo` and `zoo`.
*`IGNORE_NAME("\\*.foo")` will ignore the literal record `*.foo`.