xml specific order

the default ordering is now defined in the py file

it's in the nature of relational databases that the same information is used in different forms and hence needs to be sorted differently to fulfill users expectations

currently the users has to click the column header to get the result (after first having to set the number of dsplayed rec to a higher number than actual records should be fixed in trunk )

Suggestion:
allow to code the sort order in the XML structure of every tree view