EpisodeWidget: Added a separator in each widget.

This is a work around since list_box_set_header_func is not yet
available in the gtk-rs bindings.

hammond-gtk/resources/gtk/episode_widget.ui

@@ -6,7 +6,17 @@
     <property name="visible">True</property>
     <property name="can_focus">False</property>
     <property name="orientation">vertical</property>
-    <property name="spacing">5</property>
+    <child>
+      <object class="GtkSeparator">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+      </object>
+      <packing>
+        <property name="expand">False</property>
+        <property name="fill">True</property>
+        <property name="position">0</property>
+      </packing>
+    </child>
     <child>
       <object class="GtkBox">
         <property name="visible">True</property>
@@ -244,7 +254,8 @@
       <packing>
         <property name="expand">True</property>
         <property name="fill">True</property>
-        <property name="position">0</property>
+        <property name="padding">5</property>
+        <property name="position">1</property>
       </packing>
     </child>
     <child>
@@ -255,7 +266,7 @@
         <property name="expand">False</property>
         <property name="fill">True</property>
         <property name="padding">5</property>
-        <property name="position">1</property>
+        <property name="position">2</property>
       </packing>
     </child>
   </object>