Also, a couple of FNIRT fixes - Jacobian option is an image and a couple of
options that were previously compulsary are now optional (because they are
not required in certain circumstances)

This is because the logic for selecting a command now checks for
a file actually existing in FSLDEVDIR, FSLDIR etc, so we need to
make sure a corresponding file actually exists before doing a command
line wrapper test

It is now a stream in its own right rather than a boolean

MNT: renamed extract_noise to fsl_ents

See merge request fsl/fslpy!72

Also fix betfparam and strongbias arguments

DOC: Changelog

See merge request fsl/fslpy!71

Bf/settings

See merge request fsl/fslpy!70

CI: Make sure doc deps are installed

See merge request fsl/fslpy!68

MNT: Post-release version bump

See merge request fsl/fslpy!67

Enh/settings set use

See merge request fsl/fslpy!66

Enh/version build number

See merge request fsl/fslpy!65

BF: Make sure only the first few bytes of the image are read when detecting memmaps

See merge request fsl/fslpy!64

Rf/save mmap

See merge request fsl/fslpy!63