Feature Request: echo value of `sh` `:out` option

Given the task foo, which uses the sh helper with Process.spawn-style options:

task "foo" do
  sh({ "FOO" => "BAR" }, "ls manuscript/*.md", out: "mdlist.txt")
end

Currently, running this task reveals environment variables in shell-command style, but not the output sink.

$ rake foo
FOO=BAR ls manuscript/*.md

Suggested behavior is to reveal the output sink as a simulated shell redirect:

$ rake foo
FOO=BAR ls manuscript/*.md > mdlist.txt

Start at the sh helper and its handling of Process.spawn-style out options, then run the foo task shown in the issue to inspect the displayed command. Done means an out: "mdlist.txt" option appears as > mdlist.txt in the simulated shell command, alongside the environment variables and command.