Rename run_again_with_refreshed_authentication?

Now it's called refresh_token_and_retry?
Rename error_for(response)

Now it's called response_error
Rename run_again_after_a_while?

Now it's split into: server_error? and sleep_and_retry?
Retry Timeout errors that may work the 2nd time

Another surprise from YouTube API: once in a while the API is
unavailable (and causes SSL Error), but after a little while it's back.
Retry more timeout errors that may work 2nd time

When YouTube times out, different errors are raised depending on
how it fails. For all of them (Errno::ETIMEDOUT, Errno::ENETUNREACH)
we can at least retry the request one before failing for good.
Merge branch 'retry-timeout'