Change RSS view layout to horizontal. Closes #5920.

Thanks Bhaalspawn for the idea.

src/gui/rss/rss.ui

@@ -74,6 +74,12 @@
    </item>
    <item>
     <widget class="QSplitter" name="splitter_h">
+     <property name="sizePolicy">
+      <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+       <horstretch>0</horstretch>
+       <verstretch>0</verstretch>
+      </sizepolicy>
+     </property>
      <property name="orientation">
       <enum>Qt::Horizontal</enum>
      </property>
@@ -94,8 +100,14 @@
        </item>
        <item>
         <widget class="QSplitter" name="splitter_v">
+         <property name="sizePolicy">
+          <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+           <horstretch>0</horstretch>
+           <verstretch>0</verstretch>
+          </sizepolicy>
+         </property>
          <property name="orientation">
-          <enum>Qt::Vertical</enum>
+          <enum>Qt::Horizontal</enum>
          </property>
          <widget class="QListWidget" name="listArticles">
           <property name="contextMenuPolicy">