added PYTHON_DEST_DIR and MATLAB_DEST_DIR cached vars

#160 (comment)
#160 (comment)

CMakeLists.txt

@@ -75,9 +75,11 @@ find_package(PythonInterp)
 find_package(PythonLibs)
 set (BUILD_PYTHON ${PYTHONLIBS_FOUND})
 if (BUILD_PYTHON)
-  if (NOT PYTHON_DEST)
+  set(PYTHON_INSTALL_DIR "" CACHE "Directory of the SIRF Python modules")
+  if (PYTHON_INSTALL_DIR)
+   set(PYTHON_DEST "${PYTHON_INSTALL_DIR }")
+  else() 
     set(PYTHON_DEST "${CMAKE_INSTALL_PREFIX}/python")
-  endif()
   message(STATUS "Python libraries found")
   message(STATUS "Location of Python modules: " ${PYTHON_DEST})
 endif()
@@ -86,10 +88,16 @@ endif()
 message(STATUS "Attempting to find MATLAB (This might launch MATLAB so might take a while)")
 FIND_PACKAGE(Matlab COMPONENTS MAIN_PROGRAM)
 set (BUILD_MATLAB ${Matlab_FOUND})
+
 if (BUILD_MATLAB)
   matlab_get_mex_suffix("${Matlab_ROOT_DIR}" MATLAB_MEX_EXT)
-  set(MATLAB_DEST "${CMAKE_INSTALL_PREFIX}/matlab")
-  message(STATUS "MATLAB libraries found")
+  set(MATLAB_INSTALL_DIR "" CACHE "Directory of the SIRF Matlab libraries")
+  if (MATLAB_INSTALL_DIR)
+   set(MATLAB_DEST "${MATLAB_INSTALL_DIR }")
+  else() 
+    set(MATLAB_DEST "${CMAKE_INSTALL_PREFIX}/matlab")
+  message(STATUS "Matlab libraries found")
+  message(STATUS "Location of Matlab libraries: " ${MATLAB_DEST})
 endif()
 
 if (NOT BUILD_MATLAB AND NOT BUILD_PYTHON)