update voltha-tracing chart to use appVersion to define jaeger image tag

* although the comment in the Chart.yaml says that appVersion is used to
  define the tag/version of the jaeger container, it actually was not
* copy/paste logic of using appVersion from Chart.yaml
  (.Values.Chart.AppVersion) in values.yaml to set tag for jaeger
  image
* also include option to globally overwrite image tag with
  .Values.global.image_tag like done for most other charts (for
  development purposes)
* increase voltha-tracing Chart version to 1.0.4
* increase voltha Chart version to please the linter

Signed-off-by: Jan Klare <jan.klare@bisdn.de>
Change-Id: Ia5753936e61b80bbf93867fcec5d30689658c0e1
Signed-off-by: Jan Klare <jan.klare@bisdn.de>
diff --git a/voltha-tracing/Chart.yaml b/voltha-tracing/Chart.yaml
index 96a8902..57c8cbd 100644
--- a/voltha-tracing/Chart.yaml
+++ b/voltha-tracing/Chart.yaml
@@ -14,7 +14,7 @@
 ---
 apiVersion: v1
 name: "voltha-tracing"
-version: "1.0.3"
+version: "1.0.4"
 description: "A Helm chart for deploying Jaeger all-in-one container for Trace data collection and analysis"
 keywords:
   - "onf"
diff --git a/voltha-tracing/values.yaml b/voltha-tracing/values.yaml
index 634cacb..5292f3f 100644
--- a/voltha-tracing/values.yaml
+++ b/voltha-tracing/values.yaml
@@ -19,7 +19,7 @@
 tracing:
   image:
     repository: "jaegertracing/all-in-one"
-    tag: "1.18"
+    tag: '{{- if hasKey .Values.global "image_tag" }}{{- if .Values.global.image_tag }}{{ .Values.global.image_tag }}{{- else }}{{ .Chart.AppVersion }}{{- end }}{{- else }}{{ .Chart.AppVersion }}{{- end }}'
     pullPolicy: "IfNotPresent"
   maxTraces: 100000
 
diff --git a/voltha/Chart.yaml b/voltha/Chart.yaml
index 05bb6b4..71c115c 100644
--- a/voltha/Chart.yaml
+++ b/voltha/Chart.yaml
@@ -14,7 +14,7 @@
 ---
 apiVersion: "v1"
 name: "voltha"
-version: "2.12.7"
+version: "2.12.8"
 description: "A Helm chart for Voltha based on K8S resources in Voltha project"
 keywords:
   - "onf"