Make contents (index) table for server, extension, app

[ghost]

I found useful extension that solves this problem for server, for Firefox.
https://addons.mozilla.org/en-US/firefox/addon/headingsmap/
It adds index, like bookmarks, which allows me to skip to any part of article, something that most or all normal wikipedia articles have. Good if you make such ability too, but for extension and app too.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be now be reviewed manually. Thank you for your contributions.

[kelson42]

Duplicate of #42