don't fail per-node diag if some process is dead
don't fail per-node diag if some process is dead

Change-Id: I1c550e70c10586821661dd7d6a0cfe29fb27667c
Reviewed-on: http://review.membase.org/6144
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Reviewed-by: Steve Yen <ef850f73f7832052d3c6d9b5ddd3a1716d9a57f1@gmail.com>
Tested-by: Dale Harvey <491ccac09a36ad1e38b698f273b84fd8efc31071@arandomurl.com>
Reviewed-by: Dale Harvey <491ccac09a36ad1e38b698f273b84fd8efc31071@arandomurl.com>

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