Convert all varchars to text

PostgreSQL works similarly with varchar and text columns. Rather than
limiting the amount of characters a column can hold simply use text
columns.

Because this sql is now PostgreSQL specific, there's no need to maintain
what was set in the mysql settings.

roles/mailserver/templates/mailserver.sql.j2

@@ -6,7 +6,7 @@ DROP TABLE IF EXISTS "virtual_domains";
 
 CREATE TABLE IF NOT EXISTS "virtual_domains" (
         "id" SERIAL,
-        "name" varchar(50) NOT NULL,
+        "name" TEXT NOT NULL,
         PRIMARY KEY ("id")
 );
 
@@ -15,8 +15,8 @@ CREATE UNIQUE INDEX name_idx ON virtual_domains (name);
 CREATE TABLE IF NOT EXISTS "virtual_users" (
         "id" SERIAL,
         "domain_id" int NOT NULL,
-        "password" varchar(106) NOT NULL,
-        "email" varchar(100) NOT NULL UNIQUE,
+        "password" TEXT NOT NULL,
+        "email" TEXT NOT NULL UNIQUE,
         PRIMARY KEY ("id"),
         FOREIGN KEY (domain_id) REFERENCES virtual_domains(id) ON DELETE CASCADE
 );
@@ -27,8 +27,8 @@ CREATE UNIQUE INDEX email_idx ON virtual_users (email);
 CREATE TABLE IF NOT EXISTS "virtual_aliases" (
         "id" SERIAL,
         "domain_id" int NOT NULL,
-        "source" varchar(100) NOT NULL,
-        "destination" varchar(100) NOT NULL,
+        "source" TEXT NOT NULL,
+        "destination" TEXT NOT NULL,
         PRIMARY KEY ("id"),
         FOREIGN KEY (domain_id) REFERENCES virtual_domains(id) ON DELETE CASCADE
 );