Add roboflow

[glenn-jocher]

Add roboflow pip package to requirements.txt Extras section, commented so not installed by default but integration available for users if package is installed.

Also reorder sections alphabetically.

🛠️ PR Summary

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🌟 Summary

Update to the requirements for enhanced functionality and additional support in YOLOv5.

📊 Key Changes

• Reordering of seaborn in the requirements list for better organization.
• Addition of albumentations>=1.0.3 as an optional dependency for advanced data augmentation.
• Addition of roboflow as a new requirement for improved dataset management and augmentation functionalities.

🎯 Purpose & Impact

• Organizing dependencies for better clarity and maintenance. 🧹
• By including albumentations, developers can use advanced augmentation techniques which could improve model accuracy and performance. 🎨
• With roboflow in the mix, users can benefit from streamlined dataset workflows, which can significantly ease the model training process. 🚀
• These changes aim to boost the YOLOv5's efficiency and user experience for a broader set of use cases.