DataReader with google source returns DataFrame with incorrect index name
Hello,

```
import pandas.io.data as web
import datetime

symbol = "AAPL"
end = datetime.datetime.now()
start = end - datetime.timedelta(days=10)
df = web.DataReader("AAPL", 'google', start, end)

df.index.name
```

is `'\xef\xbb\xbfDate'` it should be only `'Date'`

\xef\xbb\xbf characters are invisible !

A quick and dirty solution is to change

```
def _retry_read_url(url, retry_count, pause, name):
    for _ in range(retry_count):
        time.sleep(pause)

        # kludge to close the socket ASAP
        try:
            with urlopen(url) as resp:
                lines = resp.read()
        except _network_error_classes:
            pass
        else:
            rs = read_csv(StringIO(bytes_to_str(lines)), index_col=0,
                          parse_dates=True)[::-1]
            # Yahoo! Finance sometimes does this awesome thing where they
            # return 2 rows for the most recent business day
            if len(rs) > 2 and rs.index[-1] == rs.index[-2]:  # pragma: no cover
                rs = rs[:-1]
            return rs

    raise IOError("after %d tries, %s did not "
                  "return a 200 for url %r" % (retry_count, name, url))
```

to

```
def _retry_read_url(url, retry_count, pause, name):
    for _ in range(retry_count):
        time.sleep(pause)

        # kludge to close the socket ASAP
        try:
            with urlopen(url) as resp:
                lines = resp.read()
        except _network_error_classes:
            pass
        else:
            rs = read_csv(StringIO(bytes_to_str(lines)), index_col=0,
                          parse_dates=True)[::-1]
            rs.index.name = 'Date'
            # Yahoo! Finance sometimes does this awesome thing where they
            # return 2 rows for the most recent business day
            if len(rs) > 2 and rs.index[-1] == rs.index[-2]:  # pragma: no cover
                rs = rs[:-1]
            return rs

    raise IOError("after %d tries, %s did not "
                  "return a 200 for url %r" % (retry_count, name, url))
```

so adding rs.index.name = 'Date'
fix the problem but it could have side effect for other datasource

Kind regards
