core: Add simple Queue convenience class based on Gee.ArrayList
core: Add simple Queue convenience class based on Gee.ArrayList

GNOME/rygel,Tarnyko/rygel,jku/rygel,GNOME/rygel,luisbg/rygel,Pelagicore/Media-Manager-Rygel-patched,Tarnyko/rygel,Pelagicore/Media-Manager-Rygel-patched,Pelagicore/Media-Manager-Rygel-patched,GNOME/rygel,jku/rygel