Merge pull request #777 from vousk/fix_stdMat_clone

bumpTexture does not have to be cloned here

src/Materials/babylon.standardMaterial.js

@@ -791,7 +791,6 @@ var BABYLON;
                 newStandardMaterial.bumpTexture = this.bumpTexture.clone();
             }
             if (this.lightmapTexture && this.lightmapTexture.clone) {
-                newStandardMaterial.bumpTexture = this.bumpTexture.clone();
                 newStandardMaterial.lightmapTexture = this.lightmapTexture.clone();
                 newStandardMaterial.useLightmapAsShadowmap = this.useLightmapAsShadowmap;
             }

src/Materials/babylon.standardMaterial.ts

@@ -957,7 +957,6 @@
                 newStandardMaterial.bumpTexture = this.bumpTexture.clone();
             }
             if (this.lightmapTexture && this.lightmapTexture.clone) {
-                newStandardMaterial.bumpTexture = this.bumpTexture.clone();
                 newStandardMaterial.lightmapTexture = this.lightmapTexture.clone();
                 newStandardMaterial.useLightmapAsShadowmap = this.useLightmapAsShadowmap;
             }