CMake broken on Linux

[ericriff]

Hi!
I was using your projet to get a hang of cmake/cpack and I've notice that it is broken on Linux.
If you want to fix if, here is an easy patch. Bassicaly the RPATH is only being set for APPLE so in linux it doesn't work.

--- a/Source/CMakeLists.txt
+++ b/Source/CMakeLists.txt
@@ -26,6 +26,8 @@ target_link_libraries(StudyPack StudyPackLib)
 file(RELATIVE_PATH EXE_TO_LIB_PATH ${CMAKE_INSTALL_FULL_BINDIR} ${CMAKE_INSTALL_FULL_LIBDIR})
 if(APPLE)
   set(STUDYPACK_RPATH "@executable_path/${EXE_TO_LIB_PATH}")
+else()
+  set(STUDYPACK_RPATH "$ORIGIN/${EXE_TO_LIB_PATH}")
 endif()
 
 set_target_properties(StudyPack