Get list of servers for JSON map from the map instead of the config.
Get list of servers for JSON map from the map instead of the config.

This prevents problems with the map and servers in the config being
out of sync.

Change-Id: Ie9d1a0f4ce552126700b46b0c00f8ebe62ced78c
Reviewed-on: http://review.northscale.com:8080/646
Reviewed-by: Steve Yen <ef850f73f7832052d3c6d9b5ddd3a1716d9a57f1@gmail.com>
Tested-by: Steve Yen <ef850f73f7832052d3c6d9b5ddd3a1716d9a57f1@gmail.com>

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