Redirect error messages to stderr
Redirect error messages to stderr

Some error messages were not redirected to stderr.
Moreover, do "exit 0" instead of "exit 1" when "help" option is passed.

Signed-off-by: Rachid Koucha <55b470430ab0f78cdba904b886a7b6e0a92ea649@gmail.com>
ss1h2a3tw/lxc,hallyn/lxc,ss1h2a3tw/lxc,ss1h2a3tw/lxc,hallyn/lxc,hallyn/lxc