Update README.md

README.md

-RenderToolbox3
+RenderToolbox4
 ==============
-RenderToolbox3 is a Matlab toolbox for doing physically based rendering for psychophysics.  For more in formation, please see the RenderToolbox3 wiki:
-https://github.com/DavidBrainard/RenderToolbox3/wiki
+RenderToolbox4 is a Matlab toolbox working with 3D scenes and physically-based renderers.  For more in formation, please see the [wiki](https://github.com/RenderToolbox3/RenderToolbox4/wiki).
 
-RenderToolbox3 Copyright (c) 2012-2013 The RenderToolbox3 Team.
-RenderToolbox3 is released under the MIT License.
-Please see LICENSE.txt for details.
- - About Us: https://github.com/DavidBrainard/RenderToolbox3/wiki/About-Us
- - Join Us: https://github.com/DavidBrainard/RenderToolbox3/wiki/Join-Us
- - Discussion forum: https://groups.google.com/forum/?hl=en#!forum/rendertoolbox3-discussion
- - Known issues: https://github.com/DavidBrainard/RenderToolbox3/issues?state=open
 
+RenderToolbox4 Copyright (c) 2012-2016 The RenderToolbox4 Team.
+RenderToolbox4 is released under the MIT License.
+Please see LICENSE.txt for details.
+ - [About Us](https://github.com/RenderToolbox3/RenderToolbox4/wiki/wiki/About-Us)
+ - [Join Us](https://github.com/RenderToolbox3/RenderToolbox4/wiki/wiki/Join-Us)
+ - [Known issues](https://github.com/RenderToolbox3/RenderToolbox4/issues)