Added line to skip over holes in server list.
Added line to skip over holes in server list.

The perf stats array returned by the server has holes in it, placed in
such a way as to make the indexes of perf stats match their server id.

Added some code to skip over these holes properly.

jdellithorpe/RAMCloudUtils,ellitron/RAMCloudTools,jdellithorpe/RAMCloudUtils,ellitron/RAMCloudTools,jdellithorpe/RAMCloudUtils,jdellithorpe/RAMCloudTools,ellitron/RAMCloudTools,jdellithorpe/RAMCloudTools