Update menus.php : Add a.alias to group

MS SQL requires a.alias in the group clause.
Fix for Plugin Manager: Plugins view showing whitespace when sidebar is collapsed
Merge pull request #4796 from sovainfo/patch-15

Update menus.php : Add a.alias to group
Merge pull request #4824 from manojLondhe/sidebar

Fix for 'Plugin Manager: Plugins' view showing white-space when sidebar is collapsed