docs(readme): add animated pip install travel-seg typing SVG under hero GIF

Author: LimHyungTae

README.md

@@ -19,6 +19,10 @@
 
   <p align="center"><img src="https://user-images.githubusercontent.com/47359642/193223368-d43133ec-c231-4e50-90e0-98aa0bf3a5df.gif" alt="travel_kitti" width="95%"/></p>
 
+  <p align="center">
+    <a href="https://pypi.org/project/travel-seg/"><img src="https://readme-typing-svg.demolab.com?background=0D1117&color=22C55E&font=Fira+Code&size=28&duration=2500&pause=800&center=true&vCenter=true&width=600&height=80&lines=%24+pip+install+travel-seg" alt="$ pip install travel-seg"/></a>
+  </p>
+
   <p><strong><em>Traversable Ground and Above-Ground Object Segmentation using Graph Representation for 3D LiDAR Scans.</em></strong></p>
 </div>