API version

With the (few) changes between webform 3 and webform 4, it would be nice for webform contrib developers if webform had an API call that returned its version number. Ie, a 3 for webform 3.x and 4 for webform 4.x. That would be a rather more reliable way of knowing which version we're dealing with that guessing based on what elements are present in the data structure we're processing.

A specific example is my case is webform_serial, which needs to assign either an array to $submission['cid']['value'] or $submission[cid][0] depending on the webform version.