Merge pull request #12340 from Ithrael/doc/Executing-helm-rollback-release-0-will-rollback-to-the-previous-release

doc:Executing helm rollback release 0 will roll back to the previous …

cmd/helm/rollback.go

@@ -32,8 +32,8 @@ const rollbackDesc = `
 This command rolls back a release to a previous revision.
 
 The first argument of the rollback command is the name of a release, and the
-second is a revision (version) number. If this argument is omitted, it will
-roll back to the previous release.
+second is a revision (version) number. If this argument is omitted or set to
+0, it will roll back to the previous release.
 
 To see revision numbers, run 'helm history RELEASE'.
 `