Clean up Makefile from original

* Add proper includes for assembler
* Add qemu and stats goals
* Hide some commands
* Whitespace fixes
* Strip final binary
* Set linker page size to 4k (allows 1M alignment)
* Kernel binary depends on linker script
Import boot code from earlier project

* Multiboot path functions (test with 'make qemu')
* Native path is unimplemented
* Common symbol is temporarily defined
Gitignore for objects
Linker script