In API audit log include the contrail-usergent, remote-ip, user
and project from the request headers.

Change-Id: I9253d65c181177941fe494c58946c12f76b5f2b0
(cherry picked from commit f64e056e2bca822ab20a2db6956158735567442d)
Merge "In API audit log include the contrail-usergent, remote-ip, user and project from the request headers." into R1.10