Fix the repo name

I accidentally named the repo 'go-shellutil' instead of 'go-shellquote'.
Rename the repo and update the README.
1 file changed
tree: 25568621d6c8e4da1df5de4b310b94a8b461c038
  1. doc.go
  2. join_test.go
  3. quote.go
  4. README