title: IPv6 validation
body: <p>I used <code>IPAddressUtil.isIPv6LiteralAddress (ipAddress)</code> method to validate IPv6, but this method fails for ipv6-address/prefix-length format (format is mentioned in <a href="https://www.rfc-editor.org/rfc/rfc4291" rel="nofollow noreferrer">RFC 4291</a> section 2.3) of IPV6.</p>
  <p>Could anyone know any validators which validate &quot; ipv6-address/prefix-length &quot;  format?</p>
  <p><strong>Legal representations of IPV6</strong></p>
  <ol>
  <li>ABCD:EF01:2345:6789:ABCD:EF01:2345:6789</li>
  <li>2001:DB8:0:0:8:800:200C:417A</li>
  <li>FF01:0:0:0:0:0:0:101</li>
  <li>0:0:0:0:0:0:0:1</li>
  <li>0:0:0:0:0:0:0:0</li>
  <li>2001:DB8::8:800:200C:417A</li>
  <li>FF01::101</li>
  <li>::1</li>
  <li>::</li>
  <li>0:0:0:0:0:0:13.1.68.3</li>
  <li>0:0:0:0:0:FFFF:129.144.52.38</li>
  <li>::13.1.68.3</li>
  <li>FFFF:129.144.52.38</li>
  <li>2001:0DB8:0000:CD30:0000:0000:0000:0000/60</li>
  <li>2001:0DB8::CD30:0:0:0:0/60</li>
  <li>2001:0DB8:0:CD30::/60</li>
  </ol>
  <h2><strong>NOT legal representations of IPV6</strong></h2>
  <ol>
  <li>2001:0DB8:0:CD3/60</li>
  <li>2001:0DB8::CD30/60</li>
  <li>2001:0DB8::CD3/60</li>
  </ol>