zshrc: readd setopt nonomatch

This reverts 5e198dcbbd29464371bd7b2b110d26ad8fa44781
("zshrc: Don't unset `nomatch' anymore") again.

Whereas "setopt nomatch" would be the right[tm] thing to do, the
behaviour is annoying everyone used to other shells than Zsh. As
we used the nonomatch setting since ages to avoid confusion
especially amongst the users comming from Bash let's keep it that
way.

Acked-by: Alexander Wirt <formorer@grml.org>
Acked-by: Christian Hofstaedtler <ch@grml.org>
Acked-by: Ulrich Dangel <mru@grml.org>
Signed-off-by: Michael Prokop <mika@grml.org>