Tweak collectd / statsd perf data collection (#337)

* Adjusts the collectd poll interval to conservative 60 seconds
* Ensures that stale counters are removed by the statsd plugin
diff --git a/ansible/roles/common/templates/etc/collectd.conf.j2 b/ansible/roles/common/templates/etc/collectd.conf.j2
index d35c338..5f8d2a1 100644
--- a/ansible/roles/common/templates/etc/collectd.conf.j2
+++ b/ansible/roles/common/templates/etc/collectd.conf.j2
@@ -5,7 +5,7 @@
 #PluginDir   "/usr/lib64/collectd"
 #TypesDB     "/usr/share/collectd/types.db"
 
-Interval     10
+Interval     60
 
 #Timeout      2
 #ReadThreads  5
diff --git a/ansible/roles/common/templates/etc/collectd.d/azure.conf.j2 b/ansible/roles/common/templates/etc/collectd.d/azure.conf.j2
index badfff7..fede4c7 100644
--- a/ansible/roles/common/templates/etc/collectd.d/azure.conf.j2
+++ b/ansible/roles/common/templates/etc/collectd.d/azure.conf.j2
@@ -11,5 +11,8 @@
   Host "::"
   Port "8125"
   DeleteSets     true
+  DeleteCounters true
+  DeleteTimers   true
+  DeleteGauges   true
   TimerPercentile 90.0
 </Plugin>