help text for add-environment: clarify shortcomings [ci skip]

cmd_add_env.go

@@ -16,9 +16,12 @@ func init() {
 	desc := `Modifies the .skeema file in an existing host directory to add a new named
 environment. For example, if ` + "`" + `skeema init` + "`" + ` was previously used to create a dir
 for a host with the default "production" environment, ` + "`" + `skeema add-environment` + "`" + `
-could be used to define a "staging" or "development" environment pointing at a different
-host and port, or perhaps a "local" environment pointing at localhost and a
-socket path.`
+could be used to define a "staging" or "development" environment pointing at a
+different host and port, or perhaps a "local" environment pointing at localhost
+and a socket path.
+
+This command currently only handles very simple cases. For many situations,
+editing .skeema files directly is a better approach.`
 
 	cmd := mybase.NewCommand("add-environment", summary, desc, AddEnvHandler)
 	cmd.AddOption(mybase.StringOption("host", 'h', "", "Database hostname or IP address"))