Escaping mysql reserved words when creating foreign keys
dupe of #98

Hi

Seems like reserved mysql words are not escaped when creating references for a table. Kind of a problem when a column is named `order`

Like so:
OrderProduct.create_table()
CREATE TABLE `orderproduct` (`id` INTEGER AUTO_INCREMENT NOT NULL PRIMARY KEY, `product_id` INTEGER NOT NULL REFERENCES product (id), `order_id` INTEGER NOT NULL REFERENCES order (id));
