1.9.14.2 "Fourteen Going On Thirteen"

This release mostly includes iOS fixes, including a beta-quality fix for #39 (this may be done, and testing this fix is part of the reason for this release) and a fully-complete fix for #40 . It also defaults to using libGDX 1.9.13, even though libGDX 1.9.14 and 1.9.15-SNAPSHOT can still be selected from the Advanced tab, and even though this is part of the 1.9.14.x line of gdx-liftoff. I just don't want to encourage people to use libGDX 1.9.14; it's too buggy and 1.9.13 has approximately the same feature-set. Gradle is updated to 6.8.3 here, and a few libraries have also been updated, like Guacamole, ShapeDrawer, and vis-ui (technically vis-ui was downgraded to be compatible with 1.9.13). I hope the 14-to-13 thing isn't too confusing, and I'm fairly confident this should work on all target platforms now, including iOS. Big thanks to @JojoIce for being so patient with the iOS issues.