MAINT: Remove ignore_exception and terminal_output traits from input specs

[effigies]

This one's going to make the most sense to look at as just the first commit as the actual change. Everything else is tests.

Fixes #2554.

[codecov-io]

Codecov Report

Merging #2618 into master will decrease coverage by 0.34%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2618      +/-   ##
==========================================
- Coverage   67.59%   67.25%   -0.35%     
==========================================
  Files         339      339              
  Lines       42820    42818       -2     
  Branches     5290     5290              
==========================================
- Hits        28946    28796     -150     
- Misses      13192    13271      +79     
- Partials      682      751      +69

Flag	Coverage Δ
#smoketests	48.32% <100%> (-2.44%)	⬇️
#unittests	65.1% <100%> (+0.01%)	⬆️

Impacted Files	Coverage Δ
nipype/interfaces/afni/preprocess.py	81.48% <ø> (-0.03%)	⬇️
nipype/interfaces/base/core.py	89.85% <ø> (+0.14%)	⬆️
nipype/interfaces/base/specs.py	93.1% <100%> (-0.04%)	⬇️
nipype/workflows/fmri/fsl/preprocess.py	72.67% <0%> (-13.39%)	⬇️
nipype/pipeline/plugins/multiproc.py	75.59% <0%> (-6.55%)	⬇️
nipype/workflows/fmri/fsl/estimate.py	61.97% <0%> (-2.82%)	⬇️
nipype/interfaces/fsl/model.py	77.91% <0%> (-2.71%)	⬇️
nipype/interfaces/fsl/preprocess.py	80.33% <0%> (-2.27%)	⬇️
nipype/workflows/fmri/spm/preprocess.py	70.4% <0%> (-2.05%)	⬇️
nipype/utils/config.py	65.21% <0%> (-1.64%)	⬇️
... and 12 more

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[effigies]

Failure was a URL download issue, not related to these changes. Can rebuild before merge, if this passes code review.

[effigies]

How do people feel about this? Need to merge master, or are we happy with tests as is?

[effigies]

Ah, @oesteban approved. Merging to get tests moving along on master.