Added
* New distance measurements in the prediction Positioning class.
* New Features on the Extractions class: predictions that are removed by any method are saved in an
attribute if they're needed for logs, etc.; get all text values for a particular label; get most
common text value for a particular label.
* Better exception handling for Workflow submissions and more flexibility on format of what is returned
(allows custom response jsons to avoid the WorkflowResult class).