highlight-stderr runs a command and highlights the stderr of that command,
while preserving the order of stdout and stderr. It sends both stdout and
stderr of the command to its stdout, making it easy to pipe to a pager or
similar.
By default, highlight-stderr will highlight stderr in bold red, and leave
stdout normal. However, you can configure highlight-stderr using the
environment variables HIGHLIGHT_STDERR and HIGHLIGHT_STDOUT, which can each
contain a color specification in git's color specification format, such as
bold white red.
highlight-stderr uses io-mux to capture
the stdout and stderr of the command.
highlight-stderr only runs on Linux.