New URL rule class

Hi Schmunk,

I think this what I request you to pull could give conflicts to the new attribute in P3Page: nameId. But I am not sure because I still used the older version with the implementation of 'seoUrl'. 

The seoUrl I really like and this Url Rule Class uses the seoUrl to parse and create url's for P3Pages.

What do you think about this? In my opinion this class could do all the creating and parsing of url's, instead of the createUrl() function in the P3Page model class...

Sincerely,
Ametad