COMPAT: py2.7 compat for Timestamp.replace
compat in Timestamp.replace when passing longs (and not ints)

xref https://github.com/statsmodels/statsmodels/issues/3349
## [Current coverage](https://codecov.io/gh/pandas-dev/pandas/pull/15030?src=pr) is 84.77% (diff: 100%)
> Merging [#15030](https://codecov.io/gh/pandas-dev/pandas/pull/15030?src=pr) into [master](https://codecov.io/gh/pandas-dev/pandas/branch/master?src=pr) will not change coverage

```diff
@@             master     #15030   diff @@
==========================================
  Files           145        145          
  Lines         51131      51131          
  Methods           0          0          
  Messages          0          0          
  Branches          0          0          
==========================================
  Hits          43345      43345          
  Misses         7786       7786          
  Partials          0          0          
```

> Powered by [Codecov](https://codecov.io?src=pr). Last update [3662413...380ace1](https://codecov.io/gh/pandas-dev/pandas/compare/366241386282272328333256b6e267a68f8133a4...380ace170de3672bd0f7e26678ec227ae406a772?src=pr)