- remove superflous members from RawRouteData, partially implements #1238
- DescriptorTable moved to BaseDescriptor.h
- added templated assignment c'tor to DescriptorConfig
- refactored check for valid input coordinates, moved to BasePlugin.h
- replaced shared_ptr's to descriptors in ViaRoutePlugin.h with unique_ptr
- implemented FindIncrementalPhantomNode in facades for a single, i.e. first result
- untangled a few includes
- JSON syntax is not scattered over several files, but one place
- Reduces code duplication
- breaking changes:
- new property in json(p) formatted response: "found_alternative": True/False
- returned filenames now response.js(on) or route.gpx
- /hello plugin returns JSON now