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/users/AppRestrictionsFragment.java

@@ -988,6 +988,7 @@ public class AppRestrictionsFragment extends SettingsPreferenceFragment implemen
                         + entry.getKey());
                 mAppList.addPreference(p);
                 p.setOnPreferenceChangeListener(AppRestrictionsFragment.this);
+                p.setIcon(R.drawable.empty_icon);
                 preference.mChildren.add(p);
                 count++;
             }