Allow to inflect association

ping @Ocramius ,

Let's say you have a "User" entity with an association "fatTweets". Convention for PHP properties is camelCased, while for URI the convention is to use "dash-separated". Therefore, if we expose the association and do "/users/1/fat-tweets" it won't match because it expects "fatTweets".

This PR always try to convert the path to camelCased before doing any check.