fix(gulp:build): fix crash upon ts type errors

TS somehow started emitting the type errors as errors that are then propagating to webpack and finally gulp. Thus need to catch and recover from thrown errors.

closes  #2039, #2110

Author: Koslun

templates/app/gulpfile.babel.js

@@ -236,6 +236,9 @@ gulp.task('webpack:dist', function() {
     const webpackDistConfig = makeWebpackConfig({ BUILD: true });
     return gulp.src(webpackDistConfig.entry.app)
         .pipe(webpack(webpackDistConfig))
+        .on('error', (err) => {
+          this.emit('end'); // Recover from errors
+        })
         .pipe(gulp.dest(`${paths.dist}/client`));
 });