*Dropped deprecated QLinkedList.
*Code cleanup.
* Memory leaks are fixed.
*Fixed setting of default apps with GLib backend.
*Fixed (recommended) apps list given by GLib backend.
*Added a XdgDefaultApps class with email client, file
manager and web browser set/get methods.
*Used Qt's fix for too big SVG icons with scale factors > 1.
*Added methods to XdgDefaultApps for getting special applications.
*Fixed unneeded URL encoding for %U/%u in "xdgdesktopfile.cpp".
OBS-URL: https://build.opensuse.org/package/show/X11:LXQt/libqt5xdg?expand=0&rev=16
