Bug in sandcastle example

Just reporting a crash in a sandcastle example.

1) go to the Cesium Inspector example in the sandcastle:

2) Click "show frustums".

3)

RuntimeError: Fragment shader failed to compile. Compile log: WARNING: 0:? : '
' : extension directive should occur before any non-preprocessor tokens
ERROR: 0:3: 'gl_FragColor' : cannot use both gl_FragData and gl_FragColor

Hello,

This is a known issue. We have a bug report open here: https://github.com/AnalyticalGraphicsInc/cesium/issues/2448

Thanks,

Hannah