indicate "Visualizer" button in doc

[diemoschwarz]

In the welcome page section 4 http://guide.sensel.com/morph/, it is not immediately clear how to launch the visualizer:

4 Launch the Visualizer

The Visualizer is the easiest way to see activity on your Morph and confirm that the hardware is communicating with your computer.

Proposal

Add a screenshot and a phrase indicating that the button is at the bottom right.