Alpha-numeric printf format (#2416)

* Implement an inspector view provider to display a component that allows setting printf format for alphanumeric items in a display layout.

* Display 'Mixed' in format input if items' formats in selection are different.

* Use lodash function to find index.

* Simplify code.

* Put the logic to disallow viewing the inspector view for multi-select in the inspector view provider as apposed to the inspector view component.

src/plugins/displayLayout/AlphanumericFormatViewProvider.js

@@ -0,0 +1,77 @@
+/*****************************************************************************
+ * Open MCT, Copyright (c) 2014-2018, United States Government
+ * as represented by the Administrator of the National Aeronautics and Space
+ * Administration. All rights reserved.
+ *
+ * Open MCT is licensed under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * http://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ * Open MCT includes source code licensed under additional open source
+ * licenses. See the Open Source Licenses file (LICENSES.md) included with
+ * this source code distribution or the Licensing information page available
+ * at runtime from the About dialog for additional information.
+ *****************************************************************************/
+
+define([
+    './components/AlphanumericFormatView.vue',
+    'vue'
+], function (AlphanumericFormatView, Vue) {
+
+    function AlphanumericFormatViewProvider(openmct, options) {
+        function isTelemetryObject(selectionPath) {
+            let selectedObject = selectionPath[0].context.item;
+            let parentObject = selectionPath[1].context.item;
+            return parentObject && 
+                parentObject.type === 'layout' &&
+                selectedObject &&
+                openmct.telemetry.isTelemetryObject(selectedObject) &&
+                !options.showAsView.includes(selectedObject.type)
+        }
+
+        return {
+            key: 'alphanumeric-format',
+            name: 'Alphanumeric Format',
+            canView: function (selection) {
+                if (selection.length === 0 || selection[0].length === 1) {
+                    return false;
+                }
+
+                return selection.every(isTelemetryObject);
+            },
+            view: function (selection) {
+                let component;
+                return {
+                    show: function (element) {
+                        component = new Vue({
+                            provide: {
+                                openmct
+                            },
+                            components: {
+                                AlphanumericFormatView: AlphanumericFormatView.default
+                            },
+                            template: '<alphanumeric-format-view></alphanumeric-format-view>',
+                            el: element
+                        });
+                    },
+                    destroy: function () {
+                        component.$destroy();
+                        component = undefined;
+                    }
+                }
+            },
+            priority: function () {
+                return 1;
+            }
+        }
+    }
+
+    return AlphanumericFormatViewProvider;
+});