Added new variable es_version_lock to define if deb/rpm package should be locked to currently installed version

defaults/main.yml

@@ -1,6 +1,7 @@
 ---
 es_major_version: "1.5"
 es_version: "1.5.2"
+es_version_lock: false
 es_start_service: true
 es_plugins_reinstall: false
 es_user: elasticsearch

tasks/main.yml

@@ -5,3 +5,5 @@
 - include: elasticsearch.yml
 - include: elasticsearch-plugins.yml
   when: es_plugins is defined
+- include: elasticsearch-version-lock.yml
+  when: es_version_lock