Add Resque.after_fork to correct problem with database connections and remove resque-ensure-connected

Remove partial support for CORS on webfinger routes and replace
it with the Rack::Cors middleware. This provides more complete
CORS support and works around a caching issue with nginx on
Heroku and potentially other reverse proxies.

CORS headers are only added if the incoming request includes
an "Origin" header, which seems to be correct according to
the CORS spec.

closes #2216

if it is in any bundler group #confused

add unicorn back in.  only use one worker process for now.  also, move chrome_frame middleware into the correct load path in lib. [ci skip]