Merge pull request #9753 from mtanda/cw_period

(cloudwatch) add period alias

public/app/plugins/datasource/cloudwatch/partials/query.parameter.html

@@ -49,6 +49,7 @@
 				<li>{{stat}}</li>
 				<li>{{namespace}}</li>
 				<li>{{region}}</li>
+				<li>{{period}}</li>
 				<li>{{YOUR_DIMENSION_NAME}}</li>
 			</ul>
 		</info-popover>