cannot import module BaggingClassifier

I tried to install scikit-mdr on an Ubuntu 14.04 Linux via pip install but got this error below. To make sure it wasn't a versions issue with scikit-learn, I did a `sudo pip install -U scikit-learn`, which completed successfully, then tried to load MDR on a python console. See below.

Any ideas?

```
Successfully installed scikit-learn
Cleaning up...
avilella@ubuntu14:~$
avilella@ubuntu14:~$ python
Python 2.7.6 (default, Oct 26 2016, 20:30:19)
[GCC 4.8.4] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from mdr import MDR
Traceback (most recent call last):
File "", line 1, in
File "/usr/local/lib/python2.7/dist-packages/mdr/__init__.py", line 23, in
from .mdr_ensemble import MDREnsemble
File "/usr/local/lib/python2.7/dist-packages/mdr/mdr_ensemble.py", line 26, in
from sklearn.ensemble import BaggingClassifier
ImportError: cannot import name BaggingClassifier
```