[MRG] Fix bug in regularized OTDA l1lp with log

[rflamary]

Types of changes

• Fixes Sinkhorn l1lp transport does not return "log" details #412
• Add some tests to check that DA classes work with log=True
• Speedup some DA tests with smaller datasets

Motivation and context / Related issue

How has this been tested (if it applies)

PR checklist

• I have read the CONTRIBUTING document.
• The documentation is up-to-date with the changes I made (check build artifacts).
• All tests passed, and additional code has been covered with new tests.
• I have added the PR and Issue fix to the RELEASES.md file.

[codecov]

Codecov Report

Merging #413 (c5c6380) into master (ac830dd) will increase coverage by 0.03%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #413      +/-   ##
==========================================
+ Coverage   93.98%   94.02%   +0.03%     
==========================================
  Files          22       22              
  Lines        5920     5924       +4     
==========================================
+ Hits         5564     5570       +6     
+ Misses        356      354       -2