added support to MYSQL 8

[vjccruz]

I tried use the package db-sync on MYSQL 8 and I got an exception on:

    private function configure()
    {
        $columns = $this->connection
            ->table('information_schema.columns')
            ->where([
                'table_schema' => $this->database,
                'table_name' => $this->table,
            ])->lists('column_name');
        ....

MYSQL 8 has UPPERCASE columns in information_schema.

My propose is convert the column name to case insensitve on function lists.