Update readme

README.md

 GitLab Runner
 =============
 
-This role will install the official GitLab Runner
+This role will install the [official GitLab Runner](https://gitlab.com/gitlab-org/gitlab-ci-multi-runner)
 
 Requirements
 ------------
@@ -12,26 +12,26 @@ This role requires Ansible 2.0 or higher.
 Role Variables
 --------------
 
-```gitlab_runner_concurrent```
+`gitlab_runner_concurrent`
 The maximum number of jobs to run concurrently.
 Defaults to the number of processor cores.
 
-```gitlab_runner_coordinator_url```
+`gitlab_runner_coordinator_url`
 The GitLab coordinator URL.
-Defaults to ```https://gitlab.com/ci```.
+Defaults to `https://gitlab.com/ci`.
 
-```gitlab_runner_registration_token```
+`gitlab_runner_registration_token`
 The GitLab registration token.
 
-```gitlab_runner_description```
+`gitlab_runner_description`
 The description of the runner.
 Defaults to the hostname.
 
-```gitlab_runner_executor```
+`gitlab_runner_executor`
 The executor used by the runner.
-Defaults to ```shell```.
+Defaults to `shell`.
 
-```gitlab_runner_tags```
+`gitlab_runner_tags`
 The tags assigned to the runner,
 Defaults to an empty list.
 
@@ -42,7 +42,24 @@ None
 
 Example Playbook
 ----------------
-
+```yaml
+- hosts: all
+  remote_user: root
+  vars_files:
+    - vars/main.yml
+  roles:
+    - { role: haroldb.gitlab-runner }
+```
+
+Inside `vars/main.yml`
+```yaml
+gitlab_runner_registration_token: 'HUzTMgnxk17YV8Rj8ucQ'
+gitlab_runner_description: 'Example GitLab Runner'
+gitlab_runner_tags:
+  - node
+  - ruby
+  - mysql
+```
 
 License
 -------