AddOrgHook add a hook to an organization.

AddRepoHook add a hook to a repo.

CheckCreateHookOption check if a CreateHookOption form is valid.

EditOrgHook edit webhook `w` according to `form`.

EditRepoHook edit webhook `w` according to `form`.

GetOrgHook get an organization's webhook.

GetRepoHook get a repo's webhook.

UserID user ID of authenticated user, or 0 if not authenticated.