On homepage, show city council info instead of near person if available

[walter]

So if you are in Austin, TX:

• instead of "Official Near You", "Austin City Council" would be displayed
• below that an avatar for the mayor or if not available a council member
• a link to more info for the city that goes to the city's overview page
• number of questions or "ask the first question" if no questions yet

Note that size wise we are constrained by the left hand column "Featured" height.

cc @davidmooreppf

[walter]

Useful for prep for opengovernment/product/issues/64.