v0.4.0

Changelog

4452c20 update dep and run go mod tidy.
19024a5 yurllib: add support for signed PKCS7 files.
fb9f039 Use GoReleaser v0.143.0.
69f89ba Use Go 1.15.
e6b8376 enhance aasa lib (#41)
d2e5ba1 css: minify sanitize.css. (#40)
21ef109 readme: add linux install instructions. (#39)
472b9dd lib: create getDomain function to simplify main func. (#38)
cad5978 snap: bump base to core20. (#37)
fa2b766 cmd: move validate to a subcommand under aasa. (#36)