Zsh case insensitive path completion

add to zshrc

zstyle ":completion:*" matcher-list \
    "m:{[:lower:][:upper:]}={[:upper:][:lower:]}" \
    "m:{[:lower:][:upper:]}={[:upper:][:lower:]} l:|=* r:|=*" \
    "m:{[:lower:][:upper:]}={[:upper:][:lower:]} l:|=* r:|=*" \
    "m:{[:lower:][:upper:]}={[:upper:][:lower:]} l:|=* r:|=*"