Fail to build with "polyclipping/clipper.hpp" not found error

[Vincent Bernat]

Hey!

The same error happens in the Travis build.

[  8%] Building CXX object CMakeFiles/emf2svg.dir/src/lib/clipperWrapper.cpp.o
/home/bernat/src/libemf2svg/src/lib/clipperWrapper.cpp:1:36: fatal error: polyclipping/clipper.hpp: No such file or directory
compilation terminated.
CMakeFiles/emf2svg.dir/build.make:254: recipe for target 'CMakeFiles/emf2svg.dir/src/lib/clipperWrapper.cpp.o' failed
make[2]: *** [CMakeFiles/emf2svg.dir/src/lib/clipperWrapper.cpp.o] Error 1
CMakeFiles/Makefile2:67: recipe for target 'CMakeFiles/emf2svg.dir/all' failed
make[1]: *** [CMakeFiles/emf2svg.dir/all] Error 2
Makefile:127: recipe for target 'all' failed
make: *** [all] Error 2

[Carpentier Pierre-Francois]

I've removed clipper/polyclip dependency as, for now, it doesn't serve any purpose (will be useful one day for complex clipping).