update count of supported microcontrollers

Author: jwcooper

index.html

@@ -103,7 +103,7 @@ <h2>Easily manage and use over 500+ Python libraries.</h2>
       <h2>Supported by all of the best microcontrollers</h2>
       <div class="tagline">
         <p>
-          CircuitPython is now supported by over 550 microcontrollers. With so many to choose from, there is sure to be a perfect board for your next project.
+          CircuitPython is now supported by over 600 microcontrollers. With so many to choose from, there is sure to be a perfect board for your next project.
         </p>
       </div>
       <div class="get-started">