Freecad install path

[Mark Brethen]

FreeCAD assumes that the Data, Doc and Mod directories are at the same level as the bin directory, which violate the port file sytem. So I propose to install freecad instead with:

-DCMAKE_INSTALL_PREFIX=${prefix}/lib/${name} \
-DCMAKE_INSTALL_MANDIR=${prefix}/share/man \
-DCMAKE_INSTALL_INFODIR=${prefix}/share/info \
-DCMAKE_INSTALL_DATADIR=${prefix}/share/${name} \
-DCMAKE_INSTALL_INCLUDEDIR=${prefix}/include/${name} \
-DCMAKE_INSTALL_DOCDIR=${prefix}/share/doc/${name}

Does the cmake portgroup augment/interfere with these variables?

Mark