Update docs for grafana-dashboards playbook

Grafyaml needs to be installed for dahboard uploading to work. So,
the browbeat installation playbook needs to be run before uploading dashboards.
This commit adds text in docs to emphasize the order in which playbooks are run.

Change-Id: Iec154f600db156907a2bf78fcb1c71b4bceb5469

doc/source/installation.rst

@@ -111,6 +111,11 @@ you deploy with aggregation.
 (Optional) Install Browbeat Grafana dashboards
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
+Browbeat uses Grafyaml to upload dashboards to Grafana. Grafyaml is installed by browbeat
+at the location pointed to by the variable `browbeat_venv` in `ansible/install/group_vars/all.yml`.
+So, you need to first run the browbeat install playbook `ansible/install/browbeat.yml` before running
+the below playbook.
+
 ::
 
   [stack@ospd ansible]$ ansible-playbook -i hosts install/grafana-dashboards.yml
@@ -159,6 +164,10 @@ From your local machine
 
 (Optional) Install Browbeat Grafana dashboards
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Browbeat uses Grafyaml to upload dashboards to Grafana. Grafyaml is installed by browbeat
+at the location pointed to by the variable `browbeat_venv` in `ansible/install/group_vars/all.yml`.
+So, you need to first run the browbeat install playbook `ansible/install/browbeat.yml` before running
+the below playbook.
 
 ::
 
@@ -397,6 +406,10 @@ environment is different and thus your configuration options will vary.
 
 (Optional) Install Browbeat Grafana dashboards
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Browbeat uses Grafyaml to upload dashboards to Grafana. Grafyaml is installed by browbeat
+at the location pointed to by the variable `browbeat_venv` in `ansible/install/group_vars/all.yml`.
+So, you need to first run the browbeat install playbook `ansible/install/browbeat.yml` before running
+the below playbook.
 
 ::