R1:ea455376e6f1

Added a link to the actual object in Herald transcript.

Summary:
We were showing all kinds of information about the object in object
transcript, but there was no link to the actual object.

Test Plan:
Checked that links were working correctly for both differential and
commit objects.

Reviewed By: epriestley
Reviewers: epriestley
CC: jungejason, epriestley
Differential Revision: 125