Make the wp-connector gem mountable

[cies]

Therefor it needs to be namespaced and made into a Rails Engine (if it is not already).

In oder to map the WP_TYPE property to our models in Rails we can do a trick: find all classes that mix in WpCache and pull their mandatory ModelName::WP_TYPE property.

This way the WpConnectorController does no longer need to be made manually, but is supplied by the gem and merely needs to be mounted in the base app.

@tolgap this is what you meant right?

[tolgap]

@cies this is indeed what I meant.
It shouldn't be that big of a difference, and will make the usage of this gem much simpler by just mounting it in your routes.rb, if the WpConnectorController can be implemented in a dynamic way, as you suggested.