CSV export issues

[trob]

If there's no data (list filtered and include filters=yes or may be limitstart > records etc.) the export is breaking:
popup sticky with "0/..."
JS error
Uncaught TypeError: Cannot read property 'err' of undefined list.js:441 (GitHub 2016-02-25)

See also http://fabrikar.com/forums/index.php?threads/csv-export-problem.43298/#post-221537
http://www.jardindelavoieromaine.org/demo2/index.php/fabrik-test?fabrikdebug=1
This list is "empty" after the broken export and reload,
fabrikdebug is not showing any filter here
but J!Debug Console session is showing limitstart":2147483647
(adding &limitstart1=0 is bringing back the records)

Maybe related to #1643

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One reason for "empty" export is:
If a CDD element is a filter element and has a "Please select" value set this is not handled as an "empty" filter (i.e. no filtering like in list view) but added to the list filters in the CSV export (if "include filters"=yes).
So the export is breaking and afterwards the list is showing "no data", the filter can be seen in fabrikdebug.