Allow action matcher strategy to be configured

[PanosCodes]

Why

Currently we use the action param from the Request object to identify the correct action but there might some kind of logic, a method for example, that directs the request to a specific action.

How

Make the action matching strategy configurable by introducing Apipie.configuration.api_action_matcher that accepts a callable object.

Example

class SomeMatchingStrategy
  self.call(controller)
     #... Matching logic
  end
end

Apipie.configuration.api_action_matcher = SomeMatchingStrategy