message: Give one more example for the --featuers CLI
  The previous example confused me because I thought that `foo-feat` is
  the syntax for `foo/feat`. The "explicit" example should clarify that.
  closes
diff: @@ -369,6 +369,9 @@ For example:
  # This command is allowed with resolver = "2", regardless of which directory
  # you are in.
  cargo build -p foo -p bar --features foo-feat,bar-feat
  +
  +# This explicit equivalent works with any resolver version:
  +cargo build -p foo -p bar --features foo/foo-feat,bar/bar-feat
  ```
  Additionally, with `resolver = "1"`, the `--no-default-features` flag only
  