DataFrame.to_records converts dates wrongly
Possibly related to #1720:

When converting a DataFrame to a recarray using `df.to_records`, date indexes are incorrectly converted.

``` python
>>> import pandas
>>> df = pandas.DataFrame([["one", "two", "three"], ["four", "five", "six"]], index=pandas.date_range("2012-01-01", "2012-01-02"))
>>> df
               0     1      2
2012-01-01   one   two  three
2012-01-02  four  five    six
>>> df.to_records()
rec.array([(datetime.datetime(1970, 1, 16, 224, 0), 'one', 'two', 'three'),
       (datetime.datetime(1970, 1, 16, 248, 0), 'four', 'five', 'six')], 
      dtype=[('index', ('<M8[ns]', {})), ('0', '|O8'), ('1', '|O8'), ('2', '|O8')])
```

Notice the dates have been converted to 1970, even though the original dates were in 2012.
