refactor: drop web installer in favor of setup via cli

This makes the installation a bit more secure by ensuring a user does not accidentally expose a way for unauthorized users to add new ssh keys to the system.

Additionally, this removes the extra HOSTNAME file to make the initial install process easier (that file was not modifiable by any dokku commands.

Closes #2247

debian/preinst

@@ -7,55 +7,8 @@ if [[ -e /usr/share/debconf/confmodule ]]; then
   . /usr/share/debconf/confmodule
 fi
 
-setup_dokku_installer() {
-  NGINX_BASE_PATH="$1"
-  NGINX_INIT_NAME="$2"
-
-  NGINX_CONF="${NGINX_BASE_PATH}/conf.d/dokku-installer.conf"
-
-  rm -f $NGINX_CONF
-  touch $NGINX_CONF
-
-  {
-    echo 'upstream dokku-installer { server 127.0.0.1:2000; }'
-    echo 'server {'
-    echo '  listen      80;'
-    echo '  location    / {'
-    echo '    proxy_pass  http://dokku-installer;'
-    echo '  }'
-    echo '}'
-  } >>$NGINX_CONF
-
-  rm -f $NGINX_BASE_PATH/sites-enabled/*
-  DOKKU_DISTRO="$(
-    . /etc/os-release >/dev/null 2>&1 || true
-    echo "$ID"
-  )"
-  case "$DOKKU_DISTRO" in
-    debian)
-      /usr/sbin/invoke-rc.d "$NGINX_INIT_NAME" reload || /usr/sbin/invoke-rc.d "$NGINX_INIT_NAME" start
-      ;;
-    ubuntu)
-      if [[ -x /usr/bin/sv ]]; then
-        /usr/bin/sv reload "$NGINX_INIT_NAME" || /usr/bin/sv start "$NGINX_INIT_NAME"
-      else
-        "/etc/init.d/$NGINX_INIT_NAME" reload || "/etc/init.d/$NGINX_INIT_NAME" start
-      fi
-      ;;
-  esac
-}
-
 case "$1" in
   install)
-    db_get "dokku/web_config"
-    if [ "$RET" = "true" ]; then
-      if [[ -x /usr/bin/openresty ]]; then
-        setup_dokku_installer "/usr/local/openresty/nginx/conf" "openresty"
-      else
-        setup_dokku_installer "/etc/nginx" "nginx"
-      fi
-    fi
-
     db_get "dokku/skip_key_file"
     if [ -z "${DEBCONF_RECONFIGURE}" ] && [ "$RET" != "true" ]; then
       db_get "dokku/key_file"