add workflow

README.md

 <h1 align="center"><strong>RAVEN2YOLO</strong></h1>
 
+<img src="workflow_raven2yolo.png" alt="WORFLOW" style="width:100%; border-radius:15px;"/>
+
 This GitHub repository was created to simplify learning YOLOv5 and to adapt it for bioacoustics. It supports a paper analyzing Humpback Whale (<i>Megaptera novaeangliae</i>) vocalizations through the automatic detection and classification of 28 units.
 
 See : [Publication]()