pipeline is a tool to help with quick iteration on complex shell pipelines.
Pipe some data into pipeline, and edit your pipeline while watching the
output in real time. When you're satisfied, hit return to have its output
piped to the next stage. Or, hit ctrl-c or escape to cancel and exit 1 with
no output.
Evaluation will be 'off' until you terminate the pipeline with a ;, making
it easier to avoid running bad intermediate commands (like, if the prefix of
a command was rm...).
Inspired by, but quite different from, https://github.com/peco/peco.
