ENH: Speedup BSpline registration part in BFit

New changes are only applied to the BSpline registration part.
Based on new changes if the output composite transform is not null, it
is applied to the moving image, and the warped moving image is passed to
the BSpline registration filter.

Used the new initialization API for BSpline reg
BUG: New baselines for 4 BFit BSpline tests
Merge pull request #87 from aghayoor/BfitBSplineNewBaselines

BUG: New baselines for 4 BFit BSpline tests
BUG: FSLTextFileCompare was failing because of text file precision

The test files for FSL conversion tests were originally written
out with default precision.  After switching to  DoubleConversion,
the values are written out at full precision, and the difference
between the two precisions was greater than 1 part in 10,000 which
was the comparison Epsilon.