Can't restore database if field has a line break

[rgaiacs]

For SQLite, the restore function is

    def restore_dump(self, dump):
        if not self.connection.is_usable():
            self.connection.connect()
        cursor = self.connection.cursor()
        for line in dump.readlines():
            try:
                cursor.execute(line.decode('UTF-8'))
            except OperationalError as err:
                warnings.warn("Error in db restore: {}".format(err))
            except IntegrityError as err:
                warnings.warn("Error in db restore: {}".format(err))

The function will not performer as expected if one field has a line break because the SQL instruction will be truncate.

From the issue #238

I get a UserWarning when running dbrestore for an sqlite database:

UserWarning: Error in db restore: unrecognized token:
And then a print of some text I have entered in a field. This only happens on Textfields that have line breaks. The rest of the db restore seems to work as expected.

[ZuluPro]

Related to #238