ui: s/Openbox Theme/Labwc Theme/

Author: johanmalm

src/maindialog.ui

@@ -105,7 +105,7 @@
           <item row="0" column="0">
            <widget class="QLabel" name="label">
             <property name="text">
-             <string>Openbox Theme</string>
+             <string>Labwc Theme</string>
             </property>
            </widget>
           </item>