add twitter handles to talk pages

[bridgetkromhout]

Expected behavior

Easy and fast to find the twitter handle for livetweeting.

Actual behavior

Even though in theory I know where it is, I find myself doing a double-take constantly when I don't see twitter handles. Then I remember oh, right - click through to the speaker page. While we won't be putting everything from the speaker page onto each talk page, the utility of a twitter handle for live tweeting is pretty crucial.

And it doesn't add too much clutter:

Reproduction Steps

Look at speaker pages and talk pages.

[mattstratton]

Why not all the rest of the icons, for consistency?

[bridgetkromhout]

None of the other icons are necessary for the fast-paced limited use case (livetweeting) that would make it useful to surface more info right on the talk page instead of requiring slower in-depth reading of a speaker's full profile.