I do a lot of HTML generation just with JavaScript and am finding myself creating `index.html` files that have code that looks like this:

     <!DOCTYPE html><html><head><script src="index.js"></script></head><body></body></html>

It would be nice to be able to do:

     browserWindow.loadHTML('<!DOCTYPE html><html><head><script src="index.js"></script></head><body></body></html>');

It would be even more awesome to do:

     browserWindow.loadScript(pathToScript);

I tried to use the `preload` option for `BrowserWindow` and using `loadURL('about:blank')`, but this has an unintended side effect of not allowing you to reference other script or CSS files using relative paths.

What do you think about proposed feature?
atom/browser/api/atom_api_web_contents.cc
content::WebContents *web_contents,
                                            mate::Handle<api::Session> session,
                                            const mate::Dictionary& options) {
  content::WebContentsObserver::Observe(web_contents);
  InitWithWebContents(web_contents, session->browser_context());
  managed_web_contents()->GetView()->SetDelegate(this);
  
  new WebContentsPreferences(web_contents, options);
  
  WebContentsPermissionHelper::CreateForWebContents(web_contents);
  
  SecurityStateTabHelper::CreateForWebContents(web_contents);
  
  WebContentsZoomController::CreateForWebContents(web_contents);
  zoom_controller_ = WebContentsZoomController::FromWebContents(web_contents);
  double zoom_factor;
  if (options.Get(options::kZoomFactor, &zoom_factor))
    zoom_controller_->SetDefaultZoomFactor(zoom_factor);
  web_contents->SetUserAgentOverride(GetBrowserContext()->GetUserAgent());
  if (IsGuest()) {
    guest_delegate_->Initialize(this);
    NativeWindow* owner_window = nullptr;
    if (options.Get("embedder", &embedder_) && embedder_) {