New release 0.5.4 (#568)

Pulls in #566 and allows building on nightly

Auto merge of #463 - servo:jdm-patch-2, r=jdm

Bump pathfinder_simd minor version.

Merge pull request #190 from asajeffrey/offwhite-svgs

Make the backgrounds of the demo SVGs off-white

Fix the magicleap app to work in LuminOS 0.96

Add support for counterclockwise winding to arcs