* moved compiled files to single subdirectory

stm32f4_library.gpr

@@ -1,7 +1,7 @@
 project STM32F4_Library is
 	for Source_Dirs use ("source", "source/f4");
-	for Object_Dir use "objects/f4";
-	for Library_Dir use "library/f4";
+	for Object_Dir use "build/objects/f4";
+	for Library_Dir use "build/library/f4";
 	for Library_Name use "stm32f4";
 	for Library_Kind use "static";
 	for Target use "arm-elf";