Get rid of string fields in prometheus output

Change-Id: I7cc64c9d62df5a64f7c7027db12576f4888d0103
diff --git a/metadata/service/agent/output/prometheus_client.yml b/metadata/service/agent/output/prometheus_client.yml
index 5537b75..57b98bb 100644
--- a/metadata/service/agent/output/prometheus_client.yml
+++ b/metadata/service/agent/output/prometheus_client.yml
@@ -6,4 +6,5 @@
           bind:
             address: 0.0.0.0
             port: 9126
+          string_as_label: false
           engine: prometheus
diff --git a/metadata/service/agent/remote/output/prometheus.yml b/metadata/service/agent/remote/output/prometheus.yml
index 2c242f4..0feb428 100644
--- a/metadata/service/agent/remote/output/prometheus.yml
+++ b/metadata/service/agent/remote/output/prometheus.yml
@@ -6,4 +6,5 @@
           bind:
             address: 0.0.0.0
             port: 9126
+          string_as_label: false
           engine: prometheus
diff --git a/telegraf/files/output/prometheus_client.conf b/telegraf/files/output/prometheus_client.conf
index eb7d7fc..bbac5f2 100644
--- a/telegraf/files/output/prometheus_client.conf
+++ b/telegraf/files/output/prometheus_client.conf
@@ -1,8 +1,11 @@
 [[outputs.prometheus_client]]
 {%- if values is defined %}
 listen = "{{ values.bind.address }}:{{ values.bind.port }}"
-{%- if values.expiration_interval is defined %}
+  {%- if values.expiration_interval is defined %}
 expiration_interval = "{{ values.expiration_interval }}"
-{%- endif %}
+  {%- endif %}
+  {%- if values.string_as_label is defined %}
+string_as_label = {{ values.string_as_label|lower }}
+  {%- endif %}
 {%- endif %}
 {%- include 'telegraf/files/input/_filters.conf' %}