Auto-detect and download Benchmark in dev and stag

Crafty Docker doesn't have access to curl, wget, netcat, etc. This
helper script adds the ability to download a file.

server-properties/helpers/curl.sh

@@ -0,0 +1,19 @@
+function __curl() {
+  read -r proto server path <<<"$(printf '%s' "${1//// }")"
+  if [ "$proto" != "http:" ]; then
+    printf >&2 "sorry, %s supports only http\n" "${FUNCNAME[0]}"
+    return 1
+  fi
+  DOC=/${path// //}
+  HOST=${server//:*}
+  PORT=${server//*:}
+  [ "${HOST}" = "${PORT}" ] && PORT=80
+
+  exec 3<>"/dev/tcp/${HOST}/$PORT"
+  printf 'GET %s HTTP/1.0\r\nHost: %s\r\n\r\n' "${DOC}" "${HOST}" >&3
+  (while read -r line; do
+   [ "$line" = $'\r' ] && break
+  done && cat) <&3
+  exec 3>&-
+}
+

server-properties/start.sh

@@ -78,6 +78,24 @@ fi
 git pull
 )
 
+#
+# Import dev-tools
+#
+if [[ "$ENV" = "dev" || "stag" ]]; then
+	echo
+	echo "checking devtools..."
+	(
+	source ./config/server-properties/helpers/curl.sh
+	cd ./world/datapacks
+	if [[ ! -f benchmark-v2-1-0.zip ]]; then
+		"missing Benchmark v2, downloading..."
+		__curl "https://files.ferdin.land/ferdinland/devtools/benchmark-v2-1-0.zip" > benchmark-v2-1-0.zip
+	fi
+	)
+	echo "devltools all good!"
+	echo
+fi
+
 #
 # Copy server-properties
 #