"Theme settings" preferences removed.

app/src/main/res/xml/preference_editor.xml

@@ -22,14 +22,6 @@
                 android:targetClass="com.xabber.android.ui.preferences.AccountList"/>
         </Preference>
 
-        <Preference
-            android:title="@string/preference_interface"
-            android:key="@string/preference_interface"
-            >
-            <intent
-                android:targetPackage="@string/application_package"
-                android:targetClass="com.xabber.android.ui.preferences.ThemeSettings"/>
-        </Preference>
         <Preference
             android:title="@string/preference_contacts"
             android:key="@string/preference_contacts"