0.9.0 release rites

test: try to fix msys (#182)

Release 0.8.8

ci: test *-gnullvm instead of *-gnu

fix CI and prepare a release

Release 0.8.5

Release 0.8.3

unix: expose with_dlerror to the end users

Useful for those who are using platform-specific openers like
`dlmopen`.

Release 0.8.1