change README on HOG tutorial

Author: x4nth055

machine-learning/hog-feature-extraction/README.md

@@ -1 +1,4 @@
-# [How to Apply HOG Feature Extraction in Python](https://www.thepythoncode.com/article/hog-feature-extraction-in-python)
+# [How to Apply HOG Feature Extraction in Python](https://www.thepythoncode.com/article/hog-feature-extraction-in-python)
+To run this:
+- `pip3 install -r requirements.txt`
+- Change the input image as you wish in `hog.py` or `hog.ipynb`.