BC: Make all Request|Response Location classes final

[Konafets]

Yesterday I came aware that I don't see any reason why there is a need to extend those classes. The locations does not change from consumer to consumer of this lib. Any major changes like how to extract a header from a HTTP message or new locations should be reflect by this lib itself.

In case you need a custom location you can still implement AbstractLocation by yourself.

As this is a breaking change, I would like to put this on discussion first. @mtdowling and @jeremeamia, what you think?