Move parsers to use base class

[chapinb]

Create a base class for the parsers.

Should contain check_ips()

    def check_ips(self, data):
        """Check data for IP addresses. Results stored in ``self.ips``.

        Args:
            data (str): String to search for IP address content.

        Returns:
            None
        """
        for ipv4 in IPv4Pattern.findall(data):
            if ipv4 not in self.ips:
                self.ips[ipv4] = 0
            self.ips[ipv4] += 1
        for ipv6 in IPv6Pattern.findall(data):
            if strip_ipv6(ipv6) not in self.ips:
                self.ips[strip_ipv6(ipv6)] = 0
            self.ips[strip_ipv6(ipv6)] += 1