Added help texts to command line options
Added help texts to command line options

jibsen/imgmin,micmro/imgmin,micmro/imgmin,rflynn/imgmin,rflynn/imgmin,pornel/imgmin,rflynn/imgmin,pornel/imgmin,pornel/imgmin,micmro/imgmin,pornel/imgmin,jibsen/imgmin,rflynn/imgmin,jibsen/imgmin,micmro/imgmin,jibsen/imgmin