Print replaced by logging in utils folder and the last files

The last of the logging pull request's series!

I'm not sure how to change this in pca.py:

```python
        print >> sys.stderr, '*' * 50
        for i in range(X.shape[0]):
            if (i + 1) % (X.shape[0] / 50) == 0:
                sys.stderr.write('|')  # suppresses newline/whitespace.
            pca_estimator.observe(X[i, :])
        print >> sys.stderr
```

And the sys.sterr was used a lot in this file. I replaced it by logger.info instead of warning or error.