tools vendored from MicroPython

- manifestfile.py
  - MicroPython manifest file parser
  - https://github.com/micropython/micropython/blob/master/tools/manifestfile.py
  - v1.29.0-preview
  - f6c7803d49a6dddb11bc91f7f6c47c4a3e6219fd
    - https://raw.githubusercontent.com/micropython/micropython/f6c7803d49a6dddb11bc91f7f6c47c4a3e6219fd/tools/manifestfile.py