doc: user remote repo navbar config

Author: inhere

_navbar.md

@@ -14,7 +14,8 @@
     repo: 'php-toolkit/pflag',
     maxLevel: 4,
     // 加载 _navbar.md
-    loadNavbar: true,
+    // loadNavbar: true,
+    loadNavbar: 'https://raw.githubusercontent.com/inhere/conf/master/docsify/php-projects.md',
     // 加载 _sidebar.md
     // loadSidebar: true,
   }