Make Sensor emit a SampleCnnfig for the Sample passed into SampleRay()
Generate samples for PathTracer
Bound the numbers of samples generated for PathTracer

Also add utility functions for falling back to rng.
Pre-allocate storage for samples

Feature-End: sample-config
Implement Rect shape

Feature-Start: rect
Use a rect for the back wall in the Cornell box example
Use a rect for the front wall in the Cornell box example
Use a rect for the top light in the Cornell box example
Use a rect for the floor in the Cornell box example
Use a rect for the left wall in the Cornell box example
Use a rect for the right wall in the Cornell box example

Feature-End: rect
Move image-related code to its own Image class

Feature-Start: image
Make Image determine the type of the file to write to from the path's extension
Implement writing an Image to a raw .bin file
Make ilium look at the extension of the input file to figure out what to do
Implement reading from a binary file and then writing to another file
Implement merging of two images with the same parameters
Accept any filename containing ".bin" as a binary file

Feature-End: image
Rework directory structure to follow go standards

http://golang.org/doc/code.html describes how code should be structured.

Feature-Start: github-export
Add LICENSE and README files

Feature-End: github-export