Reenabling tests using SingularityHub

[yarikoptic]

In effect Reverting 9e488cf
but it was easier to do this way.

Closes #91

Also fixed up one previously skipped test for pytest migration.

[codeclimate]

Code Climate has analyzed commit cad4019 and detected 0 issues on this pull request.

View more on Code Climate.

[codecov]

Codecov Report

Merging #180 (cad4019) into master (120bff7) will increase coverage by 3.96%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #180      +/-   ##
==========================================
+ Coverage   90.00%   93.96%   +3.96%     
==========================================
  Files          19       19              
  Lines         880      878       -2     
==========================================
+ Hits          792      825      +33     
+ Misses         88       53      -35     

Impacted Files	Coverage Δ
datalad_container/tests/test_run.py	100.00% <100.00%> (+25.95%)	⬆️
datalad_container/version.py	100.00% <100.00%> (ø)
datalad_container/containers_add.py	91.60% <0.00%> (+0.69%)	⬆️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

[yarikoptic]

good. Adds to coverage. Not sure if worth discussing, thus will proceed