New tiles system in GSV & threejs update

Hi, thanks for this helper!

Apparently the new panorama tiles system use much more tiles and higher quality so the getTileData send wrong value and the panorama show up only 1/4 of the full image.

Example at `let location = [48.8296942, 2.2615041]`

Quick fix before exploring more the problem on a larger panorama sets.
```
//getPanoramaTiles
var data = getTileData(zoom, opt.tiles)
data.rows*=2
data.columns*=2
```
```
gl.bindTexture(gl.TEXTURE_2D, handle)
gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 8192, 4096,0, gl.RGBA, gl.UNSIGNED_BYTE, null)
```

also to make the gpu example work for the current threejs ( v117 )
```
renderer.initTexture(tex)
let gl = renderer.getContext()
let handle = renderer.properties.get(tex).__webglTexture
```

Start at getPanoramaTiles and getTileData, then inspect the GPU example's texture initialization and WebGL context access. Reproduce the Paris location case and compare the tile dimensions with the panorama output. Done means the full panorama renders with the newer tile system and the GPU example works with three.js v117.

Written by the indexing model from the issue text.