Changes to allow python distutils instalation to play nicely with CPack

src/python/CMakeLists.txt

@@ -3,12 +3,15 @@ configure_file(
     ${CMAKE_CURRENT_SOURCE_DIR}/setup.py
 )
 
-if (PYTHON_INSTALL_PREFIX)
-    install(CODE "execute_process(
-        COMMAND ${PYTHON_EXECUTABLE} setup.py install --prefix ${PYTHON_INSTALL_PREFIX}
-        WORKING_DIRECTORY \"${CMAKE_CURRENT_SOURCE_DIR}\")")
-else()
-    install(CODE "execute_process(COMMAND ${PYTHON_EXECUTABLE} setup.py install
-       WORKING_DIRECTORY \"${CMAKE_CURRENT_SOURCE_DIR}\")")
+if (NOT DEFINED PYTHON_INSTALL_PREFIX)
+    set(PYTHON_INSTALL_PREFIX ${CMAKE_INSTALL_PREFIX})
 endif()
 
+install(CODE "execute_process(
+    COMMAND ${PYTHON_EXECUTABLE} setup.py install --prefix ${PROJECT_BINARY_DIR}/python_install --install-layout deb
+    WORKING_DIRECTORY \"${CMAKE_CURRENT_SOURCE_DIR}\")")
+
+install (
+    DIRECTORY ${PROJECT_BINARY_DIR}/python_install/
+    DESTINATION ${CMAKE_INSTALL_PREFIX} 
+)