Add tea whoami command (#426)

The User print will be used in future for list of users for admin

Co-authored-by: Matti R <matti@mdranta.net>
Reviewed-on: https://gitea.com/gitea/tea/pulls/426
Reviewed-by: Norwin <noerw@noreply.gitea.io>
Reviewed-by: Alexey 〒erentyev <axifive@noreply.gitea.io>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-committed-by: techknowlogick <techknowlogick@gitea.io>

main.go

@@ -35,6 +35,7 @@ func main() {
 		&cmd.CmdLogin,
 		&cmd.CmdLogout,
 		&cmd.CmdAutocomplete,
+		&cmd.CmdWhoami,
 
 		&cmd.CmdIssues,
 		&cmd.CmdPulls,