* Added "extra_capability" as a separate "Required capability" field. WIP. In the free version, we'll have just this field and no advanced "Permissions" dialog.
* Fixed a bug where the capability drop-down list would briefly show up and then immediately disappear.
* Update version number, re-added screenshots to trunk.

git-svn-id: https://plugins.svn.wordpress.org/admin-menu-editor/trunk@762959 b8457f37-d9ea-0310-8a92-e5e31aec5664