Fix: 'complete' event not tracked properly
Fix: 'complete' event not tracked properly

 - Remove 'complete' event tracking from setProgress method as we can't rely on time-updates for video completion
 - Add an explicit 'complete' method to the tracker (to be called by a video 'ended' event listener)

mpotra/vast-client-js,nathschmidt/vast-client-js,guardian/vast-client-js,selam/vast-client-js,tubemogul/vast-client-js,michaelvial/vast-client-js,SponsorPay/vast-client-js,spodlecki/vast-client-js,kaltura/vast-client-js,AltitudeDigital/vast-client-js,sclements/vast-client-js,VidRoll/vast-client-js,dailymotion/vast-client-js,stevennick/vast-client-js