Add Pacto URI class

this class will hold all URI parsing and normalizing logic currently
present on the Request class
Add scheme normalization to Pacto:URI
Add query parameters to the uri
Integrate uri with request
Better encapsulation for the uri
So heuristic! Such Smart! Wow!
We can safely return the Addressable uri
Merge pull request #95 from thoughtworks/uri_bug

Extracting uri parsing code on Request class to it's own class