Add option to disable SMTP auth

Closes #61

SQL/mysql.initial.sql

@@ -32,6 +32,10 @@ CREATE TABLE IF NOT EXISTS `ident_switch`
 	`smtp_port`
 		int
 		CHECK(`smtp_port` > 0 AND `smtp_port` <= 65535),
+	`smtp_auth`
+        smallint
+        NOT NULL
+        DEFAULT 1,
 	`drafts_mbox`
 		varchar(64),
 	`sent_mbox`

SQL/mysql/2020060100.sql

@@ -0,0 +1,7 @@
+ALTER TABLE
+  `ident_switch`
+ADD COLUMN
+	`smtp_auth`
+        smallint
+        NOT NULL
+        DEFAULT 1;

SQL/postgres.initial.sql

@@ -34,6 +34,10 @@ CREATE TABLE ident_switch
     smtp_port
 		integer
 		CHECK(smtp_port > 0 AND smtp_port <= 65535),
+	smtp_auth
+        smallint
+        NOT NULL
+        DEFAULT(1),
     drafts_mbox
         varchar(64),
     sent_mbox

SQL/postgres/2020060100.sql

@@ -0,0 +1,7 @@
+ALTER TABLE
+  ident_switch
+ADD COLUMN
+	smtp_auth
+        smallint
+        NOT NULL
+        DEFAULT(1);