CORE-37 - Added Chef-generated `.gitignore`.
CORE-37 - Updated `.gitignore` to exclude workspace / RubyMine files.
Revert "CORE-37 - Updated `.gitignore` to exclude workspace / RubyMine files."

This reverts commit 69e17cef58985304c8f72cf5d4b7caf78197114f.
CORE-37 - Updated `.gitignore` to exclude workspace / RubyMine files.
CORE-37 - Added Chef workspace `/chef-repo`.
CORE-37 - Added *Getting Started* subsection to the README.