Turn on optimization flags based on build type

cmake/Modules/UseOptimization.cmake

@@ -0,0 +1,19 @@
+# - Turn on optimizations based on build type
+
+include (AddOptions)
+
+# if we are building a debug target, then disable all optimizations
+# otherwise, turn them on. indicate to the code what we have done
+# so it can turn on assertions etc.
+if (CMAKE_COMPILER_IS_GNUCXX)
+  add_options (
+	ALL_LANGUAGES
+	"Debug"
+	"-O0" "-DDEBUG"
+	)
+  add_options (
+	ALL_LANGUAGES
+	"Release;RelWithDebInfo;MinSizeRel"
+	"-O3" "-DNDEBUG" "-flto"
+	)
+endif (CMAKE_COMPILER_IS_GNUCXX)