Use Diffy as avatar for the Gerrit server itself

Display Diffy as avatar for comments on changes that were created
by the Gerrit server, e.g. for the comment that is created if a change
needs to be rebased due to a path conflict.

Change-Id: I9bdd2e356fa1562ac1a20c4c9d17a557094d9018
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
3 files changed