Fix add button display property and add tooltips

* Add tooltips to list add buttons of instance groups, instances, and applications.

awx/ui/client/features/applications/applications.strings.js

@@ -16,6 +16,10 @@ function ApplicationsStrings (BaseString) {
         USERS: t.s('Tokens')
     };
 
+    ns.tooltips = {
+        ADD: t.s('Create a new Application')
+    };
+
     ns.add = {
         PANEL_TITLE: t.s('NEW APPLICATION')
     };

awx/ui/client/features/applications/list-applications.controller.js

@@ -38,6 +38,10 @@ function ListApplicationsController (
         vm.applicationsCount = dataset.count;
     });
 
+    vm.tooltips = {
+        add: strings.get('tooltips.ADD')
+    };
+
     vm.getModified = app => {
         const modified = _.get(app, 'modified');
 

awx/ui/client/features/applications/list-applications.view.html

@@ -24,6 +24,8 @@
                     ui-sref="applications.add"
                     class="at-Button--add"
                     id="button-add"
+                    aw-tool-tip="{{vm.tooltips.add}}"
+                    data-placement="top"
                     aria-haspopup="true"
                     aria-expanded="false">
                 </button>