Introduce new syntax for grafana.grafana.grafana

The variables has been changed inside the grafana collection.
https://github.com/grafana/grafana-ansible-collection/pull/232/files#diff-36ec1c12a8b78a7ac6941eda2d889535557fd49cffed5020cef3883174e41febR42

Thanks for pointing out @afeefghannam89
fixes #7

ansible/vars/grafana.yml

@@ -1,12 +1,16 @@
 ---
-grafana_security:
-  admin_user: admin
-  admin_password: admin
-  allow_embedding: true
-grafana_auth:
-  anonymous:
-    enabled: true
-    org_role: Viewer
+grafana_ini:
+  security:
+    admin_user: admin
+    admin_password: admin
+    allow_embedding: true
+  auth:
+    anonymous:
+      enabled: true
+      org_role: Viewer
+  log:
+    mode: syslog
+    level: warn
 
 grafana_datasources:
   - name: "Local CarbonApi"

requirements.yml

@@ -10,4 +10,5 @@ collections:
   - name: tbauriedel.gographite
   - name: tbauriedel.influxdb2
   - name: grafana.grafana
+    version: 5.7.0
   - name: community.grafana