added diagnostics for tracking down badarith in basic_stats
added diagnostics for tracking down badarith in basic_stats

Change-Id: Iadc6d490e84e78db10c74bfdb0821eed50048a9d
Reviewed-on: http://review.membase.org/6413
Reviewed-by: Steve Yen <ef850f73f7832052d3c6d9b5ddd3a1716d9a57f1@gmail.com>
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>

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