build: add builtin lib

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Add support for ruby commands

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
ruby: add libgit wrappers

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Rewrite 'reset' in ruby

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>