Set correct IP Type when adding IP TLO for URI - URL

In most cases, the type of the new IP TLO will match the type of the Indicator from which it is derived. However, if the Indicator is a URI - URL, the code must determine if the IP is IPv4 or IPv6 and set the appropriate IP Type.
Merge pull request #350 from brlogan/patch-4

Set correct IP Type when adding IP TLO for URI - URL