Merge pull request #8 from doo/fix_win32_qt_version

Fix Win32 Qt version reference
Initialize "used" variable
Merge pull request #9 from doo/fix_variable_init

Initialize "used" variable
fix overrides of default debug settings
Add LOG4QT_EXPORT to appender classes
Merge pull request #12 from doo/fix_debug_settings_and_export

Fix debug settings and export
Merge remote-tracking branch 'origin/master' into add_file_changed_signal

Conflicts:
	src/log4qt/dailyrollingfileappender.h