Add Facebook like/share feature

- After user likes something, they'll be able to share it on their wall.
- Commit includes some ugly CSS positioning we'll want to fix later.

Pivotal: relates to [73360464] - ability to share council matters.
Merge remote-tracking branch 'upstream/master'
Put pushpin atop label for “Mesa” in Leaflet

Pivotal: [Fixes 73433352]
Improve visual hierarchy

- separates the district from the councilmember part
- moves councilmember info and social stuff to left for better left-to-right readability (should read like “you live in district 3. your councilmember is ___. Here’s what he’s up to” although we actually just say “council is considering these nearby items”).

Pivotal: [Fixes #73433590]
Fix bug where twitter links added to page weren’t rendered as buttons.

Pivotal: [Fixes #73439914]
Follow the real CfA Tom Buckley.
Force rendering of Facebook like buttons 

Pivotal: [Fixes #73439914]
Removed share button

- twitter/facebook cover that functionality
- we can add some kind of “email someone” functionality later
- just keeping the working parts (fb/twitter) for now
hacked multiple icons
merged hacky icons with orange removal of Share