add sort key snippet

Change-Id: I0facdfe0fa6010d15fceeb4153faae200bd779e0

sc/uiconfig/scalc/ui/sortkey.ui

+<?xml version="1.0" encoding="UTF-8"?>
+<interface>
+  <!-- interface-requires gtk+ 3.0 -->
+  <object class="GtkFrame" id="SortKeyFrame">
+    <property name="visible">True</property>
+    <property name="can_focus">False</property>
+    <property name="label_xalign">0</property>
+    <property name="shadow_type">none</property>
+    <child>
+      <object class="GtkGrid" id="grid1">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="row_spacing">6</property>
+        <property name="column_spacing">6</property>
+        <child>
+          <object class="GtkComboBox" id="sortlb">
+            <property name="visible">True</property>
+            <property name="can_focus">False</property>
+            <property name="valign">center</property>
+            <property name="hexpand">True</property>
+          </object>
+          <packing>
+            <property name="left_attach">0</property>
+            <property name="top_attach">0</property>
+            <property name="width">1</property>
+            <property name="height">2</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkRadioButton" id="up">
+            <property name="label" translatable="yes">_Ascending</property>
+            <property name="use_action_appearance">False</property>
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="receives_default">False</property>
+            <property name="use_action_appearance">False</property>
+            <property name="use_underline">True</property>
+            <property name="xalign">0</property>
+            <property name="active">True</property>
+            <property name="draw_indicator">True</property>
+            <property name="group">down</property>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">0</property>
+            <property name="width">1</property>
+            <property name="height">1</property>
+          </packing>
+        </child>
+        <child>
+          <object class="GtkRadioButton" id="down">
+            <property name="label" translatable="yes">_Descending</property>
+            <property name="use_action_appearance">False</property>
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="receives_default">False</property>
+            <property name="use_action_appearance">False</property>
+            <property name="use_underline">True</property>
+            <property name="xalign">0</property>
+            <property name="draw_indicator">True</property>
+            <property name="group">up</property>
+          </object>
+          <packing>
+            <property name="left_attach">1</property>
+            <property name="top_attach">1</property>
+            <property name="width">1</property>
+            <property name="height">1</property>
+          </packing>
+        </child>
+      </object>
+    </child>
+    <child type="label">
+      <object class="GtkLabel" id="sortft">
+        <property name="visible">True</property>
+        <property name="can_focus">False</property>
+        <property name="label" translatable="yes">Sort key </property>
+        <attributes>
+          <attribute name="weight" value="bold"/>
+        </attributes>
+      </object>
+    </child>
+  </object>
+</interface>