is broken in FSL 6.0.0-6.0.5.2, due to issues with fslorient/fslswapdim. Also
test an alternate recipe which should work across all FSL versions

conventions.

machine. Save runEddy output to file so we can inspect it on failures

code is shared across all tests in a common "runEddy" script. Also test both
$FSLDIR/bin/eddy_openmp and $FSLDIR/bin/eddy_cpu if either exist.

FEAT analysis

The random element of running GPS is taken out by using precomputed gradient orientations.
The old implementation set a random subset of bvecs to b=0 (or to b=2000).
This is now fixed ensuring that the full bvecs are used for each shell.