Point not found files to edge documentation even if we didn't specified the version

[rafaelfranca]

Example of failing URL: http://api.rubyonrails.org/classes/ActiveJob/QueueAdapters.html.

I believe we should try to redirect it to edgeapi like we are doing if we use this URL http://api.rubyonrails.org/v4.2.0/classes/ActiveJob/QueueAdapters.html.

@fxn WDYT?

[fxn]

There you go! 😄