Make jsoncpp includes less dependent on how jsonccp is packaged

[RemiLacroix-IDRIS]

Hello,

Would it be possible to modify the jsoncpp includes so that they are less dependent on how jsoncpp is packaged?

Currently #include <jsoncpp/json/json.h> is used but if you install jsoncpp manually, there won't be any jsoncpp top folder, just <installdir>/include/json. It would be great if you could switch to #include <json/json.h> instead.

Best regards,
Rémi Lacroix