add coverage test for travis
coverall added
remove whitespace, fix pip install
FIX scipy API
... add the fix to import check
Merge pull request #2497 from dengemann/extend_fast_dot

FIX: support older scipy API for fast_dot
AdaBoostRegressor: fix redundant recalculation of error_vect.max()
Merge pull request #2500 from ndawe/r2

[MRG] AdaBoostRegressor: fix redundant recalculation of error_vect.max()
Merge pull request #2495 from jaquesgrobler/ENH_coverage_travis

add coverage test for travis