Cannot fetch all milestones

I want to fetch all milestones even if the data span multiple pages.
However, currently it fetches only first 30 records.
Then I checked source code and found `listMilestones` method uses `this._request` method ([code](https://github.com/github-tools/github/blob/22b889cd48cd281812b020d85f8ea502af69ddfd/lib/Issue.js#L146))
while other listing methods like `listIssues` use `this._requestAllPages`.
Is this intended?

### Versions

- Node - 6.2.0
- github-api - 3.0.0

Start in lib/Issue.js at the listMilestones method referenced by the issue, then compare its request path with listIssues and the _requestAllPages method. Confirm how milestone pagination is handled and verify that fetching milestones returns records from every page rather than only the first 30.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.