added pandas 0.22 and sklearn 0.19 to tox.

Author: arielrossanigo

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = {py27,py36}-sklearn{17,18}
+envlist = {py27,py36}-sklearn{17,18,19}-pandas{19,22}
 
 [testenv]
 deps =
@@ -9,9 +9,11 @@ deps =
     flake8==2.4.1
     numpy==1.14.3
     scipy==0.18.1
-    pandas==0.19.2
+    pandas19: pandas==0.19.2
+    pandas22: pandas==0.22.0
     sklearn17: scikit-learn==0.17.1
     sklearn18: scikit-learn==0.18.1
+    sklearn19: scikit-learn==0.19.1
     py27: mock==1.3.0
 
 commands =