In a discussion we had yesterday, Ludovic mentioned the need to pass a
special flag to the cmake configure phase to modify the rpath of installed
libraries, as done for the package slim. I then noticed I needed the same
flag for clucene. The attached patch applies it globally in the cmake build
system. This should also avoid the need for the add-libs-to-runpath phase
in the gmsh package Eric Bavier posted yesterday.

In slim, there is another flag:
    ;; Don't build libslim.so, because then the build
    ;; system is unable to set the right RUNPATH on the
    ;; 'slim' binary.
    "-DBUILD_SHARED_LIBS=OFF"
I wonder if we should instead use another of the rpath setting variables
given at
   http://www.cmake.org/Wiki/CMake_RPATH_handling

Moreover, libclucene-core.so needs to be linked to libclucene-shared.so.1
from the same package. Here we usually employ patchelf, but maybe yet again
a cmake flag could solve the problem directly.

Comments from cmake specialists are very welcome!

Andreas