Write out sorted symbols, excluding inherited ones on private classes

There are cases where a private class may inherit an exportable member (e.g. ol.DebugTile_#getTileCoord comes from ol.Tile#getTileCoord).  We want to avoid making these exportable.

buildcfg/jsdoc/symbols/publish.js

@@ -1,6 +1,7 @@
 /**
  * @fileoverview Generates JSON output based on doclets with the "api" tag.
  */
+var assert = require('assert');
 var fs = require('fs');
 var path = require('path');
 
@@ -16,20 +17,25 @@ exports.publish = function(data, opts) {
   // get all doclets with the "api" property.
   var docs = data({api: {isString: true}}).get();
 
-  process.stdout.write('{"symbols": [');
-
-  // stream JSON for each doclet
-  docs.forEach(function(doc, i) {
-    var metadata = {
+  // get sorted symbols, filter out those that are members of private classes
+  var symbols = docs.filter(function(doc) {
+    var include = true;
+    var constructor = doc.memberof;
+    if (constructor && constructor.substr(-1) === '_') {
+      assert.strictEqual(doc.inherited, true,
+          'Unexpected export on private class: ' + doc.longname);
+      include = false;
+    }
+    return include;
+  }).map(function(doc) {
+    return {
       name: doc.longname,
-      extends: doc.augments || [],
-      package: doc.api,
       path: path.join(doc.meta.path, doc.meta.filename)
     };
-    var sep = i > 0 ? ',' : '';
-    process.stdout.write(sep + JSON.stringify(metadata));
+  }).sort(function(a, b) {
+    return a.name < b.name ? -1 : 1;
   });
 
-  process.stdout.write(']}\n');
+  process.stdout.write(JSON.stringify({symbols: symbols}, null, 2));
 
 };