ENH: Add "logFileReport" to BRAINSFit

A file to write out final information report in CSV file:
MetricName,MetricValue,FixedImageName,FixedMaskName,MovingImageName,MovingMaskName
Merge pull request #17 from aghayoor/BRAINSFitWithReport

ENH: Add "logFileReport" flag to BRAINSFit