Electron v1.3.3 发布，跨平台桌面应用开发工具

Electron v1.3.3 发布了，Electron.js 是 Github 发布跨平台桌面应用开发工具，基于 Web 技术。

本次发布改进如下：

Changelog:

Remove the view-painted event which was introduced in v1.3.1 and didn't work. #6705
Add support for offscreen rendering. #6691, #6713, #6723, #6721, #6737, #6741
Add win.setContentBounds(options[, animate]) and win.getContentBounds() APIs. #6654
Add image.getBitmap() API. #6733
Add zoomin, zoomout, resetzoom to MenuItem's roles. #6777
Fix the remote devtools page not loading in Electron. #6707
Fix cookies API not working for custom protocols. #6708
Fix properties of DOM objects not being able to be sent via ipc module. #6776

macOS

Add systemPreferences.isSwipeTrackingFromScrollEventsEnabled() API. #6686
Add systemPreferences.postNotification(event, userInfo) andsystemPreferences.postLocalNotification(event, userInfo) APIs. #6752
Add more details to error message of autoUpdater. #6743
Add startspeaking and stopspeaking to MenuItem's roles. #6765
Fix resizable: false option disabling the fullscreen button. #6664
Fix scroll-touch-begin and scroll-touch-end events being emitted when scrolling page.#6754

Windows

Add return value for app.setUserTasks(tasks) API. #6766
Add win.setThumbnailToolTip(toolTip) API. #6762
Fix calling autoUpdate.checkForUpdates() for twice making quitAndInstall() throw errors.#6780
Fix win.setThumbnailClip(region) API not recognizing high-DPI displays. #6782