Add a SAVE method for Processing Rules in API

Now that certification for Processing Rules is no longer required, it should be time to open up a Save method for processing rules in the API

Presently the only method available is 'ViewProcessingRules' in the 'ReportSuite' API

As a company with dozens of active RSIDs with standardized Processing Rules, a change in one rule set is a pain to roll out everywhere

Having a Save method for Processing rules would make it easy to update across Report Suites, as it is done now with variables/events