Describes a changeset / commit.
- The author of the changeset
- The timestamp of the changeset. Precision is in seconds
- the repository that this changeset belongs to. For reasons of performance and conciseness this field may
be null depending on the service used to construct this changeset. If an explicit repository context has been
provided by some other mechanism (for example, web-fragments on the changeset page will have an explicit
'repository' object in their render context) it is preferable to use that instead of this method.