Simple Go-based setuid+setgid+setgroups+exec
copied from cf-staging / gosuThis is a simple tool grown out of the simple fact that su and sudo
have very strange and often annoying TTY and signal-forwarding behavior.
They're also somewhat complex to setup and use (especially in the case of
sudo), which allows for a great deal of expressivity, but falls flat if
all you need is "run this specific application as this specific user and
get out of the pipeline".
