v3.8.0

Commit	Message/Description
9b7289c	3.8.0
bc8bcb9	Add CI badges to README
59ae578	xs: minor cleanups
5bd0252	Add XS test engine
984b439	runtimes/d8.js: introduce V8's own harness agent (includes license)
2886010	Add License file
2a06d71	Safely replace occurrences of $ in runtimes/*.js code.