Fix crash on close #255
Fix #484

Missing tooltip
Fix travis compilation with osx+qt5

Homebrew currently installs qt 5.4.0
Merge pull request #503 from ctrlaltca/travis_osx_qt5

Fix travis compilation with osx+qt5
Merge pull request #502 from ctrlaltca/fix_484

Fix #484: Missing tooltip
Merge pull request #501 from ctrlaltca/crash_on_exit

Fix crash on close #255