builds and installs nginx; also removes the 'Server'-Tag
prereqs: up and running nginx (e.g. sudo dnf install nginx)
Fedora prereqs: sudo dnf install gcc-c++ pcre-devel zlib-devel make wget openssl-devel libxml2-devel libxslt-devel gd-devel perl-ExtUtils-Embed GeoIP-devel gperftools-devel redhat-rpm-config
usage: ./nginx_build.sh $version [optional: $server_name] (e.g. ./nginx_build.sh 1.13.2 apache)