Bug 7932 [Revised] Twitter share doesn't work with socialnetworks

Bug 7932 [Revised] Twitter share doesn't work with socialnetworks

The only way I can get this to work consistently is to use
Twitter's own code as documented here:

https://dev.twitter.com/docs/tweet-button

This requires that we use the tweet button generated by Twitter
rather than the smaller image we were using before. Using the
documented options for generating a custom button produced the
same inconsistent behavior this patch attempts to fix.

Because of the change of appearance I moved the Twitter button
to last in line so that similarly-sized buttons were grouped. I
also changed the configuration of the Google+ button to exclude
the count, saving some horizontal space.

Revision removes explicit declaration of share URL. I think when
testing this previously I assumed it was required when in fact
the share URL wasn't working because it was a localhost address.

Localhost addresses are apparently rejected by Twitter. Testers
beware.

Signed-off-by: Nicole C. Engard <nengard@bywatersolutions.com>
Passed-QA-by: Paul Poulain <paul.poulain@biblibre.com>
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>