Free the limits on type "String" fields#482

When creating or editing a column, data type “String” is available but is limited (sight unseen) to 256 characters. I’d like to see an option to allow strings of any size. MySQL certainly allows it with type VARCHAR(length). Please make this a feature for formatting column data types. I can’t live with limited strings on the website I’m building for a client. If there’s a way around this limit, please advise.