Release - making the release configuration compile

Note: these are just basic changes for the already exisiting Release|Win32 configuration. we will need to rethink and consolidate the build when we start buildning for other architectures/platforms
Break-Up[Explicit] - clean up/refactoring

- moving url and querystring from connection to connection_impl
- marking ctors with 1 mandatory parameter as explicit to prevent from implicit conversions
- moving implementations from headers to cpp files

No functional changes