Wayland Weston Compositor's Next Version Will Be v3.0

With the recent Wayland 1.13 release, the Weston reference compositor broke tradition of being the same version as Wayland due to having ABI breakage that forced them to bump the version to 2.0. With the next release, it won't be Weston 2.1 but now Weston 3.0 due to additional ABI breaks for libweston...