I am currently working with go-github sdk, and I noticed some inconsistencies in the types of time fields. Some fields are *time.Time while others are *Timestamp.

For example, this difference can be spotted in the PullRequest and Projects struct. It is also littered around the codebase. In my opinion, let's stick to one type for time fields which is *Timestamp.

if this is seen as a valid issue, I will open a PR to fix it.

Thanks.