LearnBoost/node-canvas — pull request #356 by selaux (2013-11-14 13:03:39+00:00)
Title: Fix filter parameter in toBuffer method

I tried to write a png to disk using a custom compressionLevel and filter method. But it always failed. I found this line in the code and it seems to me that the filter is using the wrong index for the parameter (```args[1]``` is compressionLevel). So I fixed it.