Added back btn class so that buttons will disable properly.
Added back btn class so that buttons will disable properly.

aconyteds/Esri-Ozone-Map-Widget,aconyteds/Esri-Ozone-Map-Widget,Esri/Esri-Ozone-Map-Widget,Esri/Esri-Ozone-Map-Widget,Esri/Esri-Ozone-Map-Widget,aconyteds/Esri-Ozone-Map-Widget,aconyteds/Esri-Ozone-Map-Widget