Distribute tarballs in XZ format instead of GZIP by default.
Distribute tarballs in XZ format instead of GZIP by default.

Automake has required options for that.
Users still can create tarball in any supported format they want.

lxde/lxmenu-data,smart2128/lxmenu-data,lxde/lxmenu-data,smart2128/lxmenu-data