[script] Add a script to create hash table for sasl (used by postfix)

scripts/update_sasl_hash_table.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+#will create saslpass.db with passwd in hash
+#smtp_sasl_password_maps=hash:/etc/postfix/salspass
+
+# debug could help with debug_peer_list = smtp_msa.orange.fr and
+# debug_peer_level =5
+sudo postmap hash:/etc/posfix/saslpass