Configuration options?

Hi,
Will you be adding any way to set config options using PHP constants or a function for values like the bucket name, path, access key and, secret? Currently they are stored in the database unencrypted. Also it’d be nice to disable setting the ‘ACL’ prop when uploading. My bucket is not publicly accessible and so don’t use/need it (CloudFront serves up the files) and I prefer to give the user’s policy as few permissions as possible.