Adding basic vmlinux identification & extraction

[rockrid3r]

Adds kernel-pwning support. Partly fixes #293

Right now it works if shell commands vmlinux-to-elf [file] [outfile] and extract-vmlinux [file] > [outfile] works.

We need to discuss how to add the vmlinux-to-elf and extract-vmlinux dependencies since they both are non-rust, so can't just append into cargo.toml.

• vmlinux-to-elf is a github repository
• extract-vmlinux is just a bash script provided in any linux source(does not depend on kernel version).

We can make it 2 ways:

• add custom initialization (post-cargo). Like "install.sh" and implement installation there
• just show in README.md how to install them both.

What do you prefer?