simplify commands in readme
simplify commands in readme

* You don't need the .git suffix to clone a repository if it is
  unambiguous.

* If you don't pass the identity file to ssh-agent, it will try the ones
  in ~/.ssh. It's less typing and more flexible because it will also
  load e.g. id_ed25519.

* You don't need -r to rm a file.

vdloo/raptiformica,vdloo/raptiformica,vdloo/raptiformica