Smudge adjustment and patch for Qt tablet in relative mode

My tablet was not responding as expected due to a Qt 4.8 bug (the famous
Wacom tablet in relative mode conflict) but there is a solution: the
changed line does exactly the same job but it prevents from large Wacom
coordinate differences.
Smudgetool fix (was not saving feather setting)
Smudge fix completion & related fixes - tool reset completion
Merge pull request #191 from eVoLuTiVeMEDIA/master

Smudge adjustment and patch for Wacom in relative mode