Merge pull request #16 from lucacasagrande/master

Template with horizontal plane
add a copy of the Apache License, Version 2.0
add a function to transform 3d world coordinates to map coordinates
update TrackballControls.js
click event for terrain
revert 57a2d4 (update TrackballControls.js) manually to fix affected dat-gui panel
use Qgis2threejs.js for common functions