Check email address

src/freedombone-base-email

     read_config_param MY_EMAIL_ADDRESS
     read_config_param DH_KEYLENGTH
 
-    MY_EMAIL_ADDRESS=${MY_USERNAME}@${DEFAULT_DOMAIN_NAME}
+    if [ ${#MY_EMAIL_ADDRESS} -lt 3 ]; then
+        MY_EMAIL_ADDRESS=${MY_USERNAME}@${DEFAULT_DOMAIN_NAME}
+    fi
 
     install_email_basic
     #install_email_with_tor