add some docs on UI customization, a jsdoc conf file, fix some class links in the doc

jsdoc.json

@@ -0,0 +1,22 @@
+{
+    "plugins": [],
+    "recurseDepth": 10,
+    "source": {
+        "includePattern": ".+\\.js(doc|x)?$",
+        "excludePattern": "(^|\\/|\\\\)_"
+    },
+    "sourceType": "module",
+    "tags": {
+        "allowUnknownTags": true,
+        "dictionaries": ["jsdoc","closure"]
+    },
+    "templates": {
+        "cleverLinks": true,
+        "monospaceLinks": true
+    },
+    "opts": {
+        "readme": "./README.md",
+        "destination": "./docs/",
+        "tutorials": "./tutorials"
+    }
+}