FIXED CXX bugs should be added not replaced

(forwarded from debian packaging patch)
Signed-off-by: Emmanuel Promayon <Emmanuel.Promayon@imag.fr>

CMakeLists.txt

@@ -31,7 +31,7 @@ include(camitk/packaging/CamiTKOpenSourcePackaging)
 camitk_opensource_packaging()
 
 # CamiTK 4.0 is C++11 compliant
-set(CMAKE_CXX_FLAGS "-std=c++11")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
 
 # Specific to SDK: first compile the SDK (it looks like a CEP but is sooooo special...)
 add_subdirectory(sdk)

imaging/actions/itkfilters/CMakeLists.txt

 if (WIN32)
     if(CMAKE_CL_64)
-        # for 64 bits platform, enable big obj (.o) handling, in ordere to correctly compile this (heavy) project
+        # for 64 bits platform, enable big obj (.o) handling, in order to correctly compile this (heavy) project
         if (MSVC)
-            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}/bigobj")
-            elseif(MINGW)
-                set(CMAKE_CXX_FLAGS "-O3 -finline-functions")
-            endif()
+            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /bigobj")
+        elseif(MINGW)
+            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O3 -finline-functions")
+        endif()
     endif()
 endif()