Change URL behaviour to match W3 spec

[neetas]

We're attempting to make requests to an API that has case sensitive endpoints. The current behaviour of the wrapper does the not match the W3 spec [1] which says that the domain name should be case insensitive, but the endpoint does not need to be case insensitive. The wrapper currently lowercases the entire url.

Tests were added after the lowercase was a thing, so there's no record of why we're lower casing it all. If this is going to break things we can try and get the endpoint fixed instead.

[1] http://stackoverflow.com/questions/7996919/should-url-be-case-sensitive

[gregsochanik]

I can't see that it will break anything, and I can only imagine it was lower-cased because (afair anyway) that was what the router was doing to urls anyway, so should be fine.

[neetas]

This release broke quite a lot of our tests. We've removed it from the NuGet search results.