"Install Update notifications plugin" message hijacks UberMenu control panel

@devs

Just a heads up. As the title says, the "Install Update notifications plugin" message hijacks the UberMenu control panel, pushing most of the menu options down and rendering them inaccessible.

Once the plugin is installed and the message is no longer displayed, the UberMenu control panel functions normally.

For those interested, UberMenu is here: http://wpmegamenu.com/