Update Churn Analysis notebook README description

Makes the description more consistent with other notebooks.

Author: donnemartin

README.md

@@ -64,7 +64,7 @@ IPython Notebook(s) used in [kaggle](https://www.kaggle.com/) competitions and b
 | Notebook | Description |
 |-------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------|
 | [titanic](http://nbviewer.ipython.org/github/donnemartin/data-science-ipython-notebooks/blob/master/kaggle/titanic.ipynb) | Predict survival on the Titanic.  Learn data cleaning, exploratory data analysis, and machine learning. |
-| [churn-analysis](http://nbviewer.ipython.org/github/donnemartin/data-science-ipython-notebooks/blob/master/analyses/churn.ipynb) | Predicts customer churn.  Exercises logistic regression, gradient boosting classifers, support vector machines, random forests, and k-nearest-neighbors.  Discussion of confusion matrices, ROC plots, feature importances, prediction probabilities, and calibration/descrimination.|
+| [churn-analysis](http://nbviewer.ipython.org/github/donnemartin/data-science-ipython-notebooks/blob/master/analyses/churn.ipynb) | Predict customer churn.  Exercise logistic regression, gradient boosting classifers, support vector machines, random forests, and k-nearest-neighbors.  Includes discussions of confusion matrices, ROC plots, feature importances, prediction probabilities, and calibration/descrimination.|
 
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