0.8.3

appimage installs now update themselves.

The AppImage compiles the tracked commit and installs it to
~/.local/share/hikari/app, and its launcher runs that build from then on.
No squashfs-tools, no rebuilding the image, no release needed for later
updates. Go is the only extra tool, and Ryoku ships it.

Reinstall once if you are on an older build, then hikari --version should
output 0.8.3 (caca5cf2). From there the Update button follows main seamlessly.