Rename legacy boot code for clarity

As the legacy boot code will be abandoned for the time being, it made
sense to rename the folder to indicate the legacy nature of the code.

i386/build.bash

@@ -11,8 +11,8 @@ cd $PROJECT_PATH/bootsector
 nasm -o $PROJECT_PATH/.build/objects/bootsector.bin \
     bootsector.asm
 
-bash $PROJECT_PATH/loader/build.bash
+bash $PROJECT_PATH/legacy-boot/build.bash
-mv $PROJECT_PATH/loader/loader.bin $PROJECT_PATH/.build/objects/loader.bin
+mv $PROJECT_PATH/legacy-boot/loader.bin $PROJECT_PATH/.build/objects/loader.bin
 
 cat $PROJECT_PATH/.build/objects/bootsector.bin > $PROJECT_PATH/nightloader.bin
 cat $PROJECT_PATH/.build/objects/loader.bin >> $PROJECT_PATH/nightloader.bin