Merge pull request #8241 from nextgenthemes/3.0.0-wip

rename '.navbar .nav' to '.navbar-nav'

less/navbar.less

@@ -281,7 +281,7 @@
     margin-left: -5px;
     margin-right: 5px;
   }
-  .navbar .nav {
+  .navbar-nav {
     float: left;
     // undo margin to make nav extend full height of navbar
     margin-top: 0;