no requirements.txt

There is no requirements file. After installing protobuf with `pip install protobuf`, running the script creates an error:
```
TypeError: Descriptors cannot not be created directly.
If this call came from a _pb2.py file, your generated code is out of date and must be regenerated with protoc >= 3.19.0.
If you cannot immediately regenerate your protos, some other possible workarounds are:
1. Downgrade the protobuf package to 3.20.x or lower.
2. Set PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=python (but this will use pure-Python parsing and will be much slower).

More information: https://developers.google.com/protocol-buffers/docs/news/2022-05-06#python-updates
```
Installing version 3.20.0, resolved this issue, `pip install protobuf==3.20.0`:
```
.\usagestats_conv.py

Android Usagestats XML Parser
By: @AlexisBrignoni
Web: abrignoni.com

Files:

Records processed: 0
Triage report completed. See Reports.html.
```
Could you add a requirements.txt file to prevent dependency issues?