Resolves: fdo#77516 sub-grid shouldn't be allowed as 0

regression from

commit 3cb6587a
Author: Csikós Tamás <csks.tomi@gmail.com>
Date:   Sun Jul 7 13:40:53 2013 +0200
    modern .ui widgetlayout for optgrid

Change-Id: I9e998ce203c16c2303e00347ce6a2992c92cc8dc

svx/uiconfig/ui/optgridpage.ui

 <?xml version="1.0" encoding="UTF-8"?>
+<!-- Generated with glade 3.16.1 -->
 <interface>
-  <!-- interface-requires gtk+ 3.0 -->
+  <requires lib="gtk+" version="3.0"/>
   <object class="GtkAdjustment" id="adjustment1">
-    <property name="upper">3.9399999999999999</property>
+    <property name="lower">0.01</property>
+    <property name="upper">10</property>
     <property name="value">1</property>
     <property name="step_increment">0.20000000000000001</property>
     <property name="page_increment">1</property>
   </object>
   <object class="GtkAdjustment" id="adjustment2">
+    <property name="lower">1</property>
     <property name="upper">99</property>
     <property name="value">2</property>
     <property name="step_increment">1</property>
     <property name="page_increment">10</property>
   </object>
   <object class="GtkAdjustment" id="adjustment3">
+    <property name="lower">1</property>
     <property name="upper">50</property>
     <property name="step_increment">1</property>
     <property name="page_increment">10</property>