Fix double HTML escaping in switcher and harden JS edge cases

SQL/mysql/2016060200.sql

@@ -1,5 +0,0 @@
-ALTER TABLE
-	`ident_switch`
-MODIFY
-	`username`
-		varchar(64);

SQL/mysql/2018071600.sql

@@ -1,6 +0,0 @@
-ALTER TABLE
-	`ident_switch`
-MODIFY
-	`username`
-		varchar(64)
-		NULL;

SQL/mysql/2018121800.sql

@@ -1,29 +0,0 @@
-ALTER TABLE
-  `ident_switch`
-CHANGE
-  `host`
-  `imap_host` varchar(64);
-
-ALTER TABLE
-  `ident_switch`
-CHANGE
-  `port`
-  `imap_port` int;
-
-ALTER TABLE
-  `ident_switch`
-ADD COLUMN
-	`smtp_host`
-    varchar(64);
-
-ALTER TABLE
-  `ident_switch`
-ADD COLUMN
-  `smtp_port`
-		int
-		CHECK(`smtp_port` > 0 AND `smtp_port` <= 65535);
-
-ALTER TABLE
-  `ident_switch`
-DROP COLUMN
-  `delimiter`;

SQL/mysql/2019112000.sql

@@ -1,5 +0,0 @@
-ALTER TABLE
-  `ident_switch`
-ADD COLUMN
-	`imap_delimiter`
-    char(1);

SQL/mysql/2019121300.sql

@@ -1,14 +0,0 @@
-ALTER TABLE
-  `ident_switch`
-ADD COLUMN
-	`drafts_mbox`
-        varchar(64),
-ADD COLUMN
-	`sent_mbox`
-        varchar(64),
-ADD COLUMN
-	`junk_mbox`
-        varchar(64),
-ADD COLUMN
-	`trash_mbox`
-        varchar(64);

SQL/mysql/2020060100.sql

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