NF: Download sample/testing data from arokem.org.
Merge pull request #6 from arokem/download_data

NF: Download sample/testing data from arokem.org.
added a voxel coordinate randomizer for shuffling the order of voxels when computing th prfs
added a voxel coordinate randomizer for shuffling the order of voxels when computing the prfs
modified the execution file so as to do a voxel-wise prf computation on the sample data.  also removed all camel case form config