fix chart title
fix chart title

Change-Id: I875d8e7a67a563c86f69510780d0b8b85bf5276a
Reviewed-on: http://review.couchbase.org/24862
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Pavel Paulau <dd88eded64e90046a680e3a6c0828ceb8fe8a0e7@gmail.com>

couchbase/cbmonitor,pavel-paulau/cbagent,vmx/cbagent,ronniedada/litmus,couchbase/cbagent,mikewied/cbagent,couchbase/cbmonitor,ronniedada/litmus