title: Unexpected token < SystemJS Production build
body: <p>I am using AngularJS writen in typescript and SystemJS module builder. 
  My app's main file (app.ts) is located inside Scripts/App.</p>
  
  <p>SytemJS production configuration from gulpfile.js:</p>
  
  <pre><code>gulp.task("deploy", ["ts", "vendorjs", "app-css"], function (done) {
  return systemBuild("./Scripts/App/app", "./dist/js/main_" + build + ".min.js");
  });
  
  function systemBuild(sourcepath, targetPath, cb) {
  var builder = new Builder();
  
  // Collection bundling
  builder.config({
      defaultJSExtensions: true,
      map: {
          "ts": "node_modules/plugin-typescript/lib/plugin.js"
      },
      baseURL: "./Scripts",
      transpiler: "ts",
      typescriptOptions: {
          module: "system",
          target: "es5",
          sourceMap: true,
          inlineSourceMap: true,
          inlineSources: true,
          resolveTypings: true,
          emitDecoratorMetadata: true,
          noImplicitAny: true,
          typeCheck: true,                // also accepts "strict"
          tsconfig: true               // also accepts a path
      },
      packages: {
          "app": {
              defaultExtension: "ts"
          }
      }
  });
  
  return builder.buildStatic(sourcepath, targetPath, {
      minify: true,
      mangle: true,
      sourceMaps: false,
      sourceMapContents: false,
      globalDefs: { DEBUG: false }
  });
  }
  </code></pre>
  
  <p>After running gulp default, I am getting 'Uncaught SyntaxError: Unexpected token &lt;' error. Could anybody tell me what I am doing wrong?</p>