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
Rework directory structure to follow go standards

http://golang.org/doc/code.html describes how code should be structured.
Add LICENSE and README files
Split off .bin merge functionality into its own executable
Decode Spectrum directly instead of going through encoding.binary.Read()
Pull the read IO from Spectrum into Weightedli
Pull the read IO from weightedLi into ReadImageFromBin()