Merge pull request #397 from tracim/buxx-patch-1

install/requirements.txt

 repoze.lru==0.7
 repoze.who==2.3
 requests==2.10.0
-six==1.8.0
+six==1.9.0
 speaklater==1.3
 sprox==0.9.4
 stevedore==1.20.0