Add voice instruction in page event

[clean99]

When users go to the new page, they don't know if the page is ready or not, we need to have voice instructions for it. Events that can add voice instruction are:

1. Jump to a new page.
2. Page loading success.
3. Page loading failed.
4. Notifications and alerts, when website show notifications and alerts, report to user.
5. Browser tab switching, read the title of the tab