More User Settings improvements

Add a menu checkbox to allow creation of users from lockscreen.
Add a delete icon in restricted profiles settings.
Other little fixes to icons.
Update some strings based on feedback.

Bug: 15761405
Bug: 16550371
Bug: 16298824

Change-Id: Ib876bd57f15c6ce2d71856f72571c6b8b0e3102d

src/com/android/settings/ApnEditor.java

@@ -446,7 +446,7 @@ public class ApnEditor extends PreferenceActivity
         // If it's a new APN, then cancel will delete the new entry in onPause
         if (!mNewApn) {
             menu.add(0, MENU_DELETE, 0, R.string.menu_delete)
-                .setIcon(R.drawable.ic_menu_delete_holo_dark);
+                .setIcon(R.drawable.ic_menu_delete);
         }
         menu.add(0, MENU_SAVE, 0, R.string.menu_save)
             .setIcon(android.R.drawable.ic_menu_save);