[Web] Add ACL + global switch to disable external alias goto

data/web/lang/lang.en-gb.json

@@ -1,6 +1,7 @@
 {
     "acl": {
         "alias_domains": "Add alias domains",
+        "alias_external_goto": "Allow aliases with external goto domains",
         "app_passwds": "Manage app passwords",
         "bcc_maps": "BCC maps",
         "delimiter_action": "Delimiter action",
@@ -444,6 +445,7 @@
         "domain_not_found": "Domain %s not found",
         "domain_quota_m_in_use": "Domain quota must be greater or equal to %s MiB",
         "extended_sender_acl_denied": "missing ACL to set external sender addresses",
+        "external_goto_denied": "External goto address %s is not allowed",
         "extra_acl_invalid": "External sender address \"%s\" is invalid",
         "extra_acl_invalid_domain": "External sender \"%s\" uses an invalid domain",
         "fido2_verification_failed": "FIDO2 verification failed: %s",