erp5_dms: rename and improve orders of PDF views

bt5/erp5_dms/ActionTemplateItem/portal_types/PDF/html_view.xml

@@ -30,7 +30,9 @@
         </item>
         <item>
             <key> <string>description</string> </key>
-            <value> <string></string> </value>
+            <value>
+              <none/>
+            </value>
         </item>
         <item>
             <key> <string>icon</string> </key>
@@ -54,7 +56,7 @@
         </item>
         <item>
             <key> <string>title</string> </key>
-            <value> <string>Preview</string> </value>
+            <value> <string>Thumbnails</string> </value>
         </item>
         <item>
             <key> <string>visible</string> </key>

bt5/erp5_dms/ActionTemplateItem/portal_types/PDF/preview.xml

@@ -56,11 +56,11 @@
         </item>
         <item>
             <key> <string>priority</string> </key>
-            <value> <float>32.5</float> </value>
+            <value> <float>10.0</float> </value>
         </item>
         <item>
             <key> <string>title</string> </key>
-            <value> <string>Reader</string> </value>
+            <value> <string>Preview</string> </value>
         </item>
         <item>
             <key> <string>visible</string> </key>