Return branch name or other build trigger in Build status webhooks

Problem Definition

The payload for the webhooks Build status created and Build status updated does not return info about the trigger of the build.

Customers who run builds on branches would like to get the branch that the build ran for automating certain processes.

Suggested Solution

Return in the webhooks payload (for Build status created and Build status updated) info about the build trigger (branch name for branch-triggered builds, pullrequest id for pull-requests triggered builds, tag for tag-triggered builds, etc)

Workaround

The payload returns the url to the vendor or system that produces the build status. If that is the URL of the build, and if an API is available for that build system, the trigger of the build could be retrieved via API.