FIX : warm_start in coordinate_descent (was ignored)
FIX : set deprecation to 0.16 in coordinate descent
API : set return_models to False by default in path functions in coordinate descent
FIX Pipeline should raise ValueError for duplicate name

It previously raised a TypeError because the construction of the
exception was done wrong. Fixes #2471.
MAINT list @paulgb's full name
FIX : get rid of convergence warning in test_coordinate_descent