Refactoring
Rake: Helper method for debugging dependency issues
Re-write track & source file models as QStandardItemModel; implement appending
configure: adjust tests for Qt5
mkvinfo: avoid compiler warnings about unused variables
fixup! configure: adjust tests for Qt5
Rakefile: add -fPIC to CXXFLAGS if compiling with Qt
mkvtoolnix-gui: port to Qt5
mkvtoolnix-gui: en/disable more controls when track selection changes
man page: add German translation of mkvtoolnix-gui.1 to repo
Merge branch 'master' into mkvtoolnix-gui
Merge branch 'qt5' into mkvtoolnix-gui
man pages: add translations of mkvtoolnix-gui.1 to repo
GUI: put a box around the right panel
GUI: Fix track column headers
build system: don't add -fPIC on Windows

…as that flag is ignored for the platform and causes warnings
GUI: implement basis of Job and MuxJob classes
GUI: remove not needed actions

For the time being the actions are defined in main_window.ui, even
though they belong into merge_widget.ui topically.
GUI: attachments tab: fix signal names in connection
GUI: attachments tab: off-by-one error when testing for overflow

Fixes removing the last line.