message: Rename "Execution speed" to "Autostep speed"
  This better reflects the actual function of the slider
diff: <item>
  <widget class="QLabel" name="label_2">
  <property name="text">
  - <string>Execution speed:</string>
  + <string>Autostep speed:</string>
  </property>
  </widget>
  </item>
  