Mark optional properties as such
Mark optional properties as such

borisyankov/DefinitelyTyped,zuzusik/DefinitelyTyped,AgentME/DefinitelyTyped,GiedriusGrabauskas/DefinitelyTyped,benishouga/DefinitelyTyped,smrq/DefinitelyTyped,arusakov/DefinitelyTyped,georgemarshall/DefinitelyTyped,mcrawshaw/DefinitelyTyped,AgentME/DefinitelyTyped,zuzusik/DefinitelyTyped,progre/DefinitelyTyped,one-pieces/DefinitelyTyped,mcrawshaw/DefinitelyTyped,georgemarshall/DefinitelyTyped,chrootsu/DefinitelyTyped,markogresak/DefinitelyTyped,magny/DefinitelyTyped,GiedriusGrabauskas/DefinitelyTyped,alexdresko/DefinitelyTyped,georgemarshall/DefinitelyTyped,jimthedev/DefinitelyTyped,QuatroCode/DefinitelyTyped,nycdotnet/DefinitelyTyped,chrootsu/DefinitelyTyped,alexdresko/DefinitelyTyped,laurentiustamate94/DefinitelyTyped,johan-gorter/DefinitelyTyped,ashwinr/DefinitelyTyped,magny/DefinitelyTyped,rolandzwaga/DefinitelyTyped,aciccarello/DefinitelyTyped,zuzusik/DefinitelyTyped,benliddicott/DefinitelyTyped,benishouga/DefinitelyTyped,jimthedev/DefinitelyTyped,mcliment/DefinitelyTyped,minodisk/DefinitelyTyped,arusakov/DefinitelyTyped,nycdotnet/DefinitelyTyped,AbraaoAlves/DefinitelyTyped,smrq/DefinitelyTyped,rolandzwaga/DefinitelyTyped,isman-usoh/DefinitelyTyped,johan-gorter/DefinitelyTyped,ashwinr/DefinitelyTyped,dsebastien/DefinitelyTyped,abbasmhd/DefinitelyTyped,AgentME/DefinitelyTyped,QuatroCode/DefinitelyTyped,minodisk/DefinitelyTyped,benishouga/DefinitelyTyped,AbraaoAlves/DefinitelyTyped,jimthedev/DefinitelyTyped,arusakov/DefinitelyTyped,progre/DefinitelyTyped,aciccarello/DefinitelyTyped,AgentME/DefinitelyTyped,georgemarshall/DefinitelyTyped,YousefED/DefinitelyTyped,AbraaoAlves/DefinitelyTyped,isman-usoh/DefinitelyTyped,dsebastien/DefinitelyTyped,amir-arad/DefinitelyTyped,abbasmhd/DefinitelyTyped,YousefED/DefinitelyTyped,aciccarello/DefinitelyTyped,borisyankov/DefinitelyTyped