Address large file with dcm2nii _parse_stdout

dcm2nii doesn't print the line _parse_stdout expects when it handles a very large file, which causes large files to be omitted from the output. This fixes that.
remove redundant imports
Added options to FSL UnaryMaths
Added Camino shredder and MESD functions in interface convert.py and odf.py respectively
Removed FSL PR from Camino PR
fix: encode empty lists
Merge pull request #805 from satra/fix/provencode

fix: encode empty lists
Merge pull request #799 from beOn/master

Address large file with dcm2nii _parse_stdout
Merge pull request #803 from mick-d/fsl

Added options to FSL UnaryMaths
Merge pull request #804 from mick-d/camino

Camino
Correction to last PR: name of Camino MESD output
Merge pull request #806 from mick-d/camino

Correction to last PR: name of Camino MESD output
Fixed tracking specs
streamline outputs generation
mandatory cannot be false
Merge pull request #809 from chrisfilo/fix/mrtrix_prob_spec

Important bugfix for MRTrix tracking
Fixed bug in FSL DTIFit interface
Proper list conversion. Closes #811
Added tests
Fix for stop argstr in MRtrix's Streamtrack interface