Fix typo in documentation for set()
Fix typo in documentation for set()

jordanyaker/polymer,yforrest/polymer,jordanyaker/polymer,MartinsThiago/polymer,mgiuffrida/polymer,Endika/polymer,ktiedt/polymer,ktiedt/polymer,ikeagold/polymer,yforrest/polymer,exlerdesigns/polymer,Polymer/polymer,ikeagold/polymer,exlerdesigns/polymer,jordanyaker/polymer,mgiuffrida/polymer,gronke/polymer,JeremybellEU/polymer,ktiedt/polymer,gazal-k/polymer,Polymer/polymer,JeremybellEU/polymer,JeremybellEU/polymer,Polymer/polymer,ikeagold/polymer,Endika/polymer,MartinsThiago/polymer,gazal-k/polymer,gronke/polymer,exlerdesigns/polymer,gronke/polymer,gazal-k/polymer,yforrest/polymer,Endika/polymer,MartinsThiago/polymer,mgiuffrida/polymer