Project Page: Twitter card support

[DarkGuardsman]

Seems to be missing on this page. Really is not needed but I think we could add some JS script to auto-generate a card per page. This way every page works on twitter regardless if we add support manually.

If we implement JS to do this it needs to detect for existing meta to avoid duplications.

[sfxworks]

This was the plan. Going to make the same injection scheme that we had before with PHP but with JS instead.