Another update of the README

fixing size of the logo and alignment of the header

Author: ahelm

README.md

@@ -1,6 +1,6 @@
 <div>
-  <img src="https://raw.githubusercontent.com/GoLP-IST/nata/master/docs/_static/nata-logo.png?token=AAKKMGXZXXRCACBKWRAZDFC6WLTBO" alt="nata logo" width=400 align="right"/>
-  <h1 align="center">Python visualization and post-processing tool for particle-in-cell codes</h1>
+  <img src="https://raw.githubusercontent.com/GoLP-IST/nata/master/docs/_static/nata-logo.png?token=AAKKMGXZXXRCACBKWRAZDFC6WLTBO" alt="nata logo" width=320 align="right"/>
+  <h1 style="text-align:left">Python visualization and post-processing tool for particle-in-cell codes</h1>
 </div>
 
 **Nata** is a python package for post-processing and visualizing simulation