Pushing out the removal of requiring $_REQUEST as part of the package.

While most if not all of the implementations that use this as their base, the $_REQUEST tag is removed in some situations from view of the PHP instance. There are many reasons for this, but supposing that this is the case the PHP SDK doesn't work.

In it's place, I've allowed for pushing additional params into the class on construction which means that if these values are present the SDK will not look to $_REQUEST in order to do that. This is useful in additional situations where frameworks mangle the $_REQUEST array.

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