Use CMake for build setup

[mayant15]

Proposal:
I am much more comfortable writing a CMakeLists.txt than a Makefile. The build system carried over from the Meaty Skeleton tutorial should be replaced by CMake.

Tasks:

• Configure CMake to use the cross-compiler
• Setup subprojects for kernel and libc
• Use the existing scripts for detecting target architecture (?)
• Profit! :D

References:

• Specify GCC path for CMake
• Mixing C and ASM
• OSDev CMake
• OSDev Hard Build System

[mayant15]

I spent some time on this today, and while things have been set up for the most part, there is an issue with specifying the assembler that CMake is supposed to use. It defaults to using /usr/bin/as and not the one we set up in $HOME/opt/cross/bin. These two pages might help

Progress is in the feat-cmake branch. Squash commits before merge.