Implemented Tag Cloud Cache Length

[Bob]

I've added an additional Tag Cloud option that lets you set the Tag Cloud Cache Length. The existing cache length is hard coded to rebuild the tag cloud cache once every 15 minutes. You can now set the length (IN MINUTES) to fit your sites performance needs. Default is set to 30 minutes. There is a minimum setting of 5 minutes.

NOTE: This can be an intensive process, so setting this option to a low minutes setting should only be done if your server can handle it.