Overhaul compiler warnings infrastructure

* Track our warnings separate from normal flags
* Remove all warnings from the SWIG code
* Add more GCC warnings

bitmap2component/CMakeLists.txt

@@ -1,6 +1,7 @@
-# .cpp files are compiled with extra ${WSHADOW_FLAGS}
-if( COMPILER_SUPPORTS_WSHADOW )
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WSHADOW_FLAGS}")
+# Add all the warnings to the files
+if( COMPILER_SUPPORTS_WARNINGS )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${WARN_FLAGS_CXX}")
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARN_FLAGS_C}")
 endif()
 
 add_definitions( -DBITMAP_2_CMP )