Remove uneeded webpack warnings;

Viewer/tests/unit/webpack.config.js

@@ -19,12 +19,6 @@ module.exports = {
             "babylonjs-viewer-assets": __dirname + '/../../src/assets/index.ts'
         }
     },
-    externals: {
-        // until physics will be integrated in the viewer, ignore cannon
-        cannon: 'CANNON',
-        oimo: 'OIMO',
-        "earcut": true
-    },
     mode: "development",
     devtool: 'source-map',
     module: {

Viewer/webpack.config.js

@@ -65,12 +65,6 @@ module.exports = /*[
                 "babylonjs-viewer-assets": __dirname + '/src/assets/index.ts'
             }
         },
-        externals: {
-            // until physics will be integrated in the viewer, ignore cannon
-            cannon: 'CANNON',
-            oimo: 'OIMO',
-            earcut: true
-        },
         mode: "development",
         devtool: 'source-map',
         plugins: [

Viewer/webpack.gulp.config.js

@@ -11,11 +11,6 @@ module.exports = {
         library: 'BabylonViewer',
         umdNamedDefine: true
     },
-    externals: {
-        cannon: 'CANNON',
-        oimo: 'OIMO',
-        "earcut": true
-    },
     resolve: {
         extensions: ['.ts', '.js'],
         alias: {