dateutil isn't included in 1.3.1

[schlamar]

According to the docs, the dateutil package should be included in the Windows installer. It was included in 1.2.0 but in the 1.3.1 installer it's missing.

If this was left out of purpose you should at least update the documentation.

[tacaswell]

The docs are wrong and have been updated on master (and will correct for 1.4 which will be released soon).