Allow to filter out packages by regex

[martinbonnin]

I'd like to exclude all symbols that are in *.internal packages. Currently it requires listing them all explicitly, would be nice to be able to specify ignoredPackages as a list of regexes:

apiValidation {
    /**
     * Exclude every package that ends with `.internal`
     */
    ignoredPackagesReegexes += "\.*\.internal"
}