Update index.html

Author: JoseRamosMendez

index.html

@@ -24,7 +24,7 @@
 <script src="navigation.js"></script>
 
 <header>
-        <h1>OpenTOPAS</h1>
+        <h1>TOPAS</h1>
         <h5>A Monte Carlo Simulation Tool for Physics, Biology and Clinical Research </h5>
         <br>
         <h3>Welcome to the TOPAS Collaboration official site!</h3>