Official Relase of VigLink-php version 0.2.0

Renamed the VigLink class to VigLinkClient, for more clarity.

Added support for sending a CUID with your URL monetization request. You can do
  this in a multitude of ways:
    1. Pass your CUID as the FOURTH parameter to the VigLinkClient constructor.
       This is NOT recommended UNLESS you intend to only monetize ONE URL with
       this given client. If you want to monetize MULTIPLE URLs, you probably
       want multiple CUIDs and should use method #3.
    2. Set the Magic Constant: '__VIGLINK_PHP_CUID__', this is almost the exact
       same as passing in the $CUID parameter to the constructor and, thusly, is
       not recommended.
    3. Pass the CUID to the monetizeURL method directly. The $cuid parameter in
       the monetizeURL method is the FOURTH parameter, if this parameter is passed
       and another CUID was set in the constructor, either via an argument or the
       magic constant, the CUID parameter trumps the constructor's CUID and it
       is uused. THIS is the PREFERRED way of setting up a CUID for your request.
       Since it is a direct call to monetize a specific URL and to do so once,
       passing the CUID here makes the client very reusable between requests and
       just makes the most sense, since it will likely change on every API hit.

Added new property to VigLinkClient, cuid.

Added new magic constant for the above property: '__VIGLINK_PHP_CUID__'.

In the monetizeURL method, if the passed in $url parameter is a string, we now
  run a filter_var on it to ensure its a valid URL. We also now check to ensure
  the $url parameter IS a string. We do the same for the $ref and $cuid parameters
  too.

Better method docblocks.