cast computed way in a proper way, add a static assertion to check for file types via traits
rename and remove include header files for stabilized lib API
fix changed include paths
change library interface to expose json container as structure to exchange data
fixed compilation of simple client

- adapted to new lib interface
- fixed return codes of command line parsing
- reformatted code
DataStructures/RawRouteData.h -> DataStructures/internal_route_result.hpp, implements #1238
install headers with .hpp suffix
install variant by default