feat: metris tab, moved data source selector

public/app/features/panel/partials/metrics.html

-<metrics-tab panel-ctrl="ctrl"></metrics-tab>

public/app/features/panel/partials/metrics_tab.html

-<div class="gf-form-group">
-  <div class="gf-form-inline">
-    <div class="gf-form">
-      <label class="gf-form-label">
-        Data Source
-      </label>
-
-      <metric-segment segment="ctrl.dsSegment"
-                      get-options="ctrl.getOptions(true)"
-                      on-change="ctrl.datasourceChanged()"></metric-segment>
-    </div>
-	</div>
-</div>
-
 <div class="query-editor-rows gf-form-group">
   <div ng-repeat="target in ctrl.panel.targets" ng-class="{'gf-form-disabled': target.hide}">
     <rebuild-on-change property="ctrl.panel.datasource || target.datasource" show-null="true">
@@ -41,16 +27,25 @@
 
 <query-troubleshooter panel-ctrl="ctrl.panelCtrl"></query-troubleshooter>
 
-<collapse-box title="Advanced Options & Data source help">
+<collapse-box title="Data Source Options">
 	<collapse-box-body>
 
 		<div class="gf-form-group">
-			<rebuild-on-change property="ctrl.panel.datasource" show-null="true">
-				<plugin-component type="query-options-ctrl">
-				</plugin-component>
-			</rebuild-on-change>
+			<div class="gf-form-inline">
+				<div class="gf-form">
+					<label class="gf-form-label">
+						Panel Data Source
+					</label>
+					<metric-segment segment="ctrl.dsSegment" get-options="ctrl.getOptions(true)" on-change="ctrl.datasourceChanged()"></metric-segment>
+				</div>
+			</div>
 		</div>
 
+		<rebuild-on-change property="ctrl.panel.datasource" show-null="true">
+			<plugin-component type="query-options-ctrl">
+			</plugin-component>
+		</rebuild-on-change>
+
 	</collapse-box-body>
 </collapse-box>