AddUser() method name

[Lxrdknows77]

In fact behaviour of this method depends if user already exists or not, and in 1st case it will just update his secret key (and status). Thus, for more transparency would be better maybe to change it to e.g CreateOrUpdateUser? Or at least add additional comment up of the method definition.

madmin-go/user-commands.go

Line 266 in f1dab86

func (adm *AdminClient) AddUser(ctx context.Context, accessKey, secretKey string) error {