Replace deprecated :to with :action in routes
Rails 4.2 deprecates route specifications with :to when they contain only an action name, issuing warnings. They should be using :action instead.
:to specifications with "controller#action" remain valid and unchanged.
fixes #13895 - replace :to with :action in routes
Using :to with a string that doesn't contain # is deprecated since
Rails 4.2, and it should instead use :action or :controller as