start adding git workflow
Merge branch 'master' of https://github.com/KumarRobotics/kr_docs into feature/add-git-workflow

Conflicts:
	docs/source/index.rst
merge with master
kr_doc: finish git workflow, add contribute page
Merge branch 'feature/add-git-workflow' of github.com:KumarRobotics/kr_docs into feature/add-setup-guide