fix for stack overflow

Recursion in item mapping iterator caused a stack
overflow for large datasets.

Task-number: QTBUG-40153
Change-Id: I693798de0ecfd3a920a3dd270172ce7ec3c13d8d
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>
Update license headers and add new license files

- Renamed LICENSE.LGPL to LICENSE.LGPLv21
- Added LICENSE.LGPLv3 & LICENSE.GPLv2
- Removed LICENSE.GPL

Change-Id: If9208b9c90bcea35bbfe6b9c10db7803e97767e0
Reviewed-by: Jani Heikkinen <jani.heikkinen@digia.com>
Merge remote-tracking branch 'origin/5.4' into dev

Change-Id: I8b1548b720d241259bb531b4742ac92d93788855