BUG: fixed df.info() output missing new line
Had this minor bug working with pandas from the command line

```
>>> df.info()
<class 'pandas.core.frame.DataFrame'>
Int64Index: 891 entries, 0 to 890
Data columns (total 12 columns):
PassengerId    891 non-null int64
# ... etc
Embarked       889 non-null object
dtypes: float64(2), int64(5), object(5)>>>
```

(The interpreter prompt is not on a new line at the end.) 

This most likely went unnoticed because pandas users tend to work in the ipython interpreter.

I had to change 2 tests, because they were not expecting the extra newline (using split('\n') and counting strings to determine if output was valid) and I don't know if that is a big issue or not.

can you squash these commits together pls
even though very minor, can you put a release note in v0.15.0
 minor comment, pls rebase and ping when green
 ping
 this looks correct to me

@jorisvandenbossche @TomAugspurger 
cc @sinhrks
 Yep; I should have noticed this when I was messing with the info repr.

Thanks @BorisVerk 
