[hooks.js] simulate Date header of response
[hooks.js] simulate Date header of response

Change-Id: I1f3688f483406cedb6926ca2406e044e1c813b9b
Reviewed-on: http://review.membase.org/3563
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Reviewed-by: Sean Lynch <9c3328a4a1f4f8f5c18b2d5b9057163c49b93ff3@literati.org>

pavel-blagodov/ns_server,vzasade/ns_server,nimishzynga/ns_server,vzasade/ns_server,t3rm1n4l/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,mschoch/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,daverigby/ns_server,membase/ns_server,nimishzynga/ns_server,nimishzynga/ns_server,ceejatec/ns_server,mschoch/ns_server,pavel-blagodov/ns_server,t3rm1n4l/ns_server,mschoch/ns_server,membase/ns_server,nimishzynga/ns_server,ceejatec/ns_server,mschoch/ns_server,daverigby/ns_server,vzasade/ns_server,ceejatec/ns_server,ceejatec/ns_server,ceejatec/ns_server,membase/ns_server,ceejatec/ns_server,pavel-blagodov/ns_server,daverigby/ns_server,nimishzynga/ns_server,mschoch/ns_server,t3rm1n4l/ns_server,membase/ns_server,vzasade/ns_server,membase/ns_server,daverigby/ns_server,pavel-blagodov/ns_server,daverigby/ns_server,membase/ns_server