Add warning to prevent installing via pip using root privileges

sudo usage is not specified in pip installation documentation.

We should add a note (a warning) to prevent sudo usage with pip.

changed milestone to %0.9.0

added Documentation label

mentioned in issue #259 (closed)

added Install label

added Easy pick label

changed milestone to %0.10.0

changed milestone to %Backlog

changed milestone to %0.11.0

assigned to @moul

marked this issue as related to #188 (closed)

Not necessary since the pipx recommendation takes over (Replace pip installation with pipx (#188 - closed)), and this is not necessary with pipx.

closed