Website: add spotify testimonials
Merge pull request #2651 from amueller/spotify_testimonial

MRG Website: add spotify testimonials
FIX silence numpy 1.8 warning for using non integer
Merge pull request #2656 from arjoly/np1.8-warnings

[MRG] FIX silence numpy 1.8 warning for using non integer
SPD: reuse variable in GaussianNB for speedup
Merge pull request #2659 from jakevdp/gaussiannb_speedup

SPD: reuse variable in GaussianNB for speedup
Merge remote-tracking branch 'upstream/master' into generative_class
address ogrisel's comments in GenerativeBayes