pflask: better errors
user: do no chdir to HOME
pty: do not print newline on finish
pflask: make --netif argument optional
docs: document --netif behaviour
Revert "pty: fix detaching when --detach is not provided"

It causes more problems than it solves.

This reverts commit 4b3ebc14c1e61796a4531627079c4c54d355c20b.

Conflicts:
	src/pty.c
pflask: better env creation