Revert "no more release config vars"

This reverts commit 1bd317cd.

bin/release

@@ -7,6 +7,15 @@ NAME=$($BIN_DIR/detect $BUILD_DIR) || exit 1
 
 cat <<EOF
 ---
+config_vars:
+  PATH: /app/.heroku/venv/bin:/bin:/usr/local/bin:/usr/bin
+  PYTHONUNBUFFERED: true
+  LIBRARY_PATH: /app/.heroku/vendor/lib
+  LD_LIBRARY_PATH: /app/.heroku/vendor/lib
+  LANG: en_US.UTF-8
+  PYTHONHASHSEED: random
+  PYTHONHOME: /app/.heroku/venv/
+  PYTHONPATH: /app/
 EOF