API: Timestamp.tz_convert/tz_localize raises Exception, should be TypeError
`Timestamp` raises normal `Exception` in case of error, and we have to catch `Exception` for error handling.

Expect `TypeError` in consistent with `DatetimeIndex`.

```
pd.Timestamp('2011-01-01').tz_convert('US/Eastern')
# Exception: Cannot convert tz-naive Timestamp, use tz_localize to localize

pd.DatetimeIndex(['2011-01-01']).tz_convert('US/Eastern')
# TypeError: Cannot convert tz-naive timestamps, use tz_localize to localize
```
