use PNG instead of JPEG for thumbnails to get better results.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@29191 20353a03-c40f-0410-a6d1-a30d3c3de9de

bt5/erp5_dms/SkinTemplateItem/portal_skins/erp5_dms/DocumentModule_viewFieldLibrary/listbox_thumbnail.xml

@@ -262,7 +262,7 @@
                 </item>
                 <item>
                     <key> <string>image_format</string> </key>
-                    <value> <string>jpg</string> </value>
+                    <value> <string>png</string> </value>
                 </item>
                 <item>
                     <key> <string>image_resolution</string> </key>

bt5/erp5_dms/bt/revision

-1037
\ No newline at end of file
+1038
\ No newline at end of file

product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/ERP5Site_viewSearchResult/listbox_thumbnail.xml

@@ -264,7 +264,7 @@
                 </item>
                 <item>
                     <key> <string>image_format</string> </key>
-                    <value> <string>jpg</string> </value>
+                    <value> <string>png</string> </value>
                 </item>
                 <item>
                     <key> <string>image_resolution</string> </key>

product/ERP5/bootstrap/erp5_core/bt/revision

-1307
\ No newline at end of file
+1308
\ No newline at end of file