Revert "REF: Remove unnecessary viz module"

[arokem]

Reverts #118

@jhlegarreta and @skoudoro : should we reconsider in light of the use of these visualizations in this CLI function? https://github.com/tee-ar-ex/trx-python/blob/master/trx/workflows.py#L276

[codecov]

Codecov Report

❌ Patch coverage is 16.32653% with 41 lines in your changes missing coverage. Please review.
✅ Project coverage is 62.15%. Comparing base (8ebbaa6) to head (bb69859).
⚠️ Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
trx/viz.py	16.32%	41 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #120   +/-   ##
=======================================
  Coverage   62.15%   62.15%           
=======================================
  Files          13       13           
  Lines        2658     2658           
=======================================
  Hits         1652     1652           
  Misses       1006     1006           

Flag	Coverage Δ
unittests	62.15% <16.32%> (ø)

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[skoudoro]

keep my position of +1 to remove, the module and the associated CLI. Not sure why the CI's did not catch it in first place.

[jhlegarreta]

I still believe that it should not be distributed with the package, but happy to chat in case my viewpoint does not faithfully represent what the purpose of the package is. I believe that the visualization CLI should dwell in DIPY.

MY bad for not having checked uses of the function across the code. PR #124 to remove the leftovers I we believe the decisions was right.

[arokem]

Could probably close this, based on outcome of the conversation on #119