Options to_*() is exporting the expiry date incorrectly

[vishalapte]

In [1]: from pandas_datareader import data as pddata

In [2]: foo = pddata.Options('aapl', 'yahoo')

In [3]: bar = foo.get_all_data()

In [4]: bar.to_csv()

'Strike,Expiry,Type,Symbol,Last,Bid,Ask,Chg,PctChg,Vol,Open_Int,IV,Root,IsNonstandard,Underlying,Underlying_Price,Quote_Time
10.0,2017-06-16,call,AAPL160617C00010000,0.0,91.0,91.45,0.0,0.0,0,0,0.0,AAPL,False,AAPL,102.52,2016-03-15 16:00:00
10.0,2017-06-16,put,AAPL160617P00010000,0.0,0.0,0.03,0.0,0.0,0,0,1.5938,AAPL,False,AAPL,102.52,2016-03-15 16:00:00
12.5,2017-06-16,call,AAPL160617C00012500,0.0,88.5,88.95,0.0,0.0,0,0,0.0,AAPL,False,AAPL,102.52,2016-03-15 16:00:00
...

ERROR: 20DD-MM-YY is erroneously being exported as Expiry instead of 20YY-MM-DD. The error is consistent across to_csv(), to_json, to_dict(), etc.

In [1]: import pandas_datareader

In [2]: pandas_datareader.version
Out[2]: '0.2.1'

[davidastephens]

This looks to be fixed with #244. Please reopen if not.