Show human-readable names for accessibility properties

Source/devtools/front_end/accessibility/module.json

 {
     "extensions": [
         {
             "title": "Accessibility",
             "type": "@WebInspector.ElementsSidebarView",
             "className": "WebInspector.AccessibilitySidebarView"
         }
     ],
     "dependencies": ["elements"],
     "experiment": "accessibilityInspection",
     "scripts": [
         "AccessibilityModel.js",
-        "AccessibilitySidebarView.js"
+        "AccessibilitySidebarView.js",
+        "AccessibilityStrings.js"
     ],
     "resources": [
         "accessibilityNode.css"
     ]
 }