This release mostly updates various libraries and adds some more that could be helpful for various types of games.
Many are improvements or fill-ins for missing features: ShapeDrawer is a high-performance replacement for ShapeRenderer in libGDX, TenPatch is an enhancement of the 9-patch support in libGDX, and Formic is a one-method library that allows String.format() to be mostly used on GWT (as Stringf.format()). Colorful-GDX allows changing colors in more ways than just multiplying channels. The Spine Runtime is selectable as a dependency, though you need a Spine license to use it outside of evaluation. Typing-Label, Artemis-ODB, SquidLib, and a few other libraries have been updated to newer versions.
This version goes back to using LWJGL3 and drops the pack task and the raw UI assets in general, though it can still copy a rudimentary skin into a project (but without needing to pack it). The gdx-tools dependency that pack added requires LWJGL2 to be used or excluded, and packing also adds a fair amount of time to a build, so now there's just a pre-built skin to enable scene2d.ui things to be used, and gdx-liftoff just copies it in.