Mail template data.

Column	Type	Constraint	Description
shop	TEXT	PRIMARY KEY	Shop ID. (shop.username)
type	TEXT		Identifier.
from	TEXT	NOT NULL	Mail address of sender.
reply_to	TEXT	NOT NULL	Mail address to reply.
disabled	INTEGER	NOT NULL	Disabled or not. 0: This type of mail will be sent. 1: It doesn't send this type of mail.

CREATE TABLE mail_template(
shop      TEXT,
type      TEXT,
"from"    TEXT     NOT NULL,
reply_to  TEXT     NOT NULL,
disabled  INTEGER  NOT NULL,
PRIMARY KEY(shop, type)
);

Multilingualized subject, header and footer of mail_template.

Column	Type	Constraint	Description
shop	TEXT	PRIMARY KEY	Shop ID. (shop.username)
template_id	TEXT		Template ID. (mail_template.type)
lang	TEXT		Language key.
subject	TEXT	NOT NULL	Mail subject.
header	TEXT	NOT NULL	Body header.
footer	TEXT	NOT NULL	Body footer.

CREATE TABLE mail_template_content(
shop         TEXT,
template_id  TEXT,
lang         TEXT,
subject      TEXT    NOT NULL,
header       TEXT    NOT NULL,
footer       TEXT    NOT NULL,
PRIMARY KEY(shop, template_id, lang)
);