Automate the Hugo release process

This commit adds a work flow aroung GoReleaser to get the Hugo release process automated and more uniform:

* It can be run fully automated or in two steps to allow for manual edits of the relase notes.
* It supports both patch and full releases.
* It fetches author, issue, repo info. etc. for the release notes from GitHub.
* The file names produced are mainly the same as before, but we no use tar.gz as archive for all Unix versions.
* There isn't a fully automated CI setup in place yet, but the release tag is marked in the commit message with "[ci deploy]"

Fixes #3358

commands/hugo.go

@@ -399,7 +399,7 @@ func InitializeConfig(subCmdVs ...*cobra.Command) (*deps.DepsCfg, error) {
 
 	if themeVersionMismatch {
 		cfg.Logger.ERROR.Printf("Current theme does not support Hugo version %s. Minimum version required is %s\n",
-			helpers.HugoReleaseVersion(), minVersion)
+			helpers.CurrentHugoVersion.ReleaseVersion(), minVersion)
 	}
 
 	return cfg, nil