six as external (#8)

* six as external

* ignore externals

.landscape.yml

@@ -2,6 +2,7 @@ doc-warnings: yes
 
 ignore-paths:
   - doc/examples
+  - mlens/externals
 
 ignore-patterns:
     - ^example/doc_.*\.py$

.travis.yml

@@ -10,6 +10,6 @@ install:
   - pip install .
 script:
   - set -e
-  - nosetests -s -v --with-coverage --exclude mlens/visualization
+  - nosetests -s -v --with-coverage --exclude mlens/visualization --exclude mlens/externals
 after_success:
   coveralls

mlens/ensemble/stacking_ensemble.py

@@ -19,7 +19,7 @@
 from ..metrics import score_matrix
 from ..parallel import preprocess_folds, preprocess_pipes
 from ..parallel import fit_estimators, base_predict
-from sklearn.externals import six
+from ..externals import six
 from time import time
 import sys
 

mlens/externals/__init__.py

@@ -0,0 +1,12 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+"""ML-ENSEMBLE
+
+author: Sebastian Flennerhag
+date: 05/02/2017
+"""
+
+import six
+
+__all__ = ['six']