added figure sup text

Author: cheind

Readme.md

@@ -14,7 +14,8 @@ Feature summary
 The figure below visualizes the basic concept of **blendtorch** used in the context of generating artificial training data for a real-world detection task.
 
 <div align="center">
-<img src="etc/blendtorch_intro_v3.svg" width="90%">
+<img src="etc/blendtorch_intro_v3.svg" width="90%"><br>
+<sup><strong>Fig 1:</strong> With Blendtorch, you are able to train your PyTorch modules on massively randomized artificial data generated by Blender simulations.</sup>
 </div>
 
 ## Getting started