aframe 1.4 support

[kfarr]

Would be nice to use in a-frame 1.4 projects. I tried to start upgrading on a new branch and fixed one small issue changing geometry.addAttribute to geometry.setAttribute in a few places.

But now there is another error beyond my understanding:

caught (in promise) TypeError: Class constructor Mesh cannot be invoked without 'new' on Line 8 of lensflare:
https://github.com/mokargas/aframe-lensflare-component/blob/master/Lensflare.js#L8