Merge pull request #183 from niamiot/master

add __repr__ to Agent / Network /Peronn
update cla doc
update ipynb TOC
Merge pull request #184 from niamiot/master

Imporvement in rays + bugfix in backtrace
bug fix:
- coverage : change default coverage file in coverage.ini (issue #185)
- ray : resolve problem when paramter value in horizontal and vertical
  plane are equal

Improvements
- localization.geometric : add __repr__ to geometric contraints and CLA
- simulnet : add __repr__ to simulnet