Compatibility with Aframe 1.3.0

[calvincs]

When using AFrame 1.3.0, the following error occurs:

aframe-websurfaces.umd.js:1 Uncaught TypeError: Class constructor Mesh cannot be invoked without 'new'
    at new n (aframe-websurfaces.umd.js:1:4354)
    at HTMLElement.<anonymous> (aframe-websurfaces.umd.js:1:7158)
    at HTMLElement.<anonymous> (aframe-v1.3.0.min.js:45177:2943)
    at i.tick (aframe-websurfaces.umd.js:1:7873)
    at HTMLElement.value (aframe-v1.3.0.min.js:45187:12868)
    at HTMLElement.value (aframe-v1.3.0.min.js:45187:13402)
    at aframe-v1.3.0.min.js:45324:132
    at onAnimationFrame (aframe-v1.3.0.min.js:20088:34)
    at onAnimationFrame (aframe-v1.3.0.min.js:9547:4)