fix pano explorer demo per `loaded` event changes
fix pano explorer demo per `loaded` event changes

RSpace/aframe,aframevr/aframe,jzitelli/aframe,mkungla/aframe,jaxmolina/ar,ngokevin/aframe,aframevr/aframe-core,fernandojsg/aframe,RSpace/aframe,weddingdj/aframe,msimpson/aframe,MatthewShotton/aframe,MatthewShotton/aframe,googlecreativelab/aframe,darkwing/aframe,chenzlabs/aframe,wizgrav/aframe,msimpson/aframe,chenzlabs/aframe,aframevr/aframe,fernandojsg/aframe,jzitelli/aframe,wizgrav/aframe,googlecreativelab/aframe,aframevr/aframe-core,jaxmolina/ar,mkungla/aframe,weddingdj/aframe,darkwing/aframe,dmarcos/aframe,dmarcos/aframe,ngokevin/aframe