asset_host_public configuration is missing from the README.md

[peterpengnz]

Hi

We have a scenario that we need to serve uploaded images as public URL.
With our current S3 bucket ACL setting, we couldn't use the aws_acl configuration option.
However, when I read the code here:

carrierwave-aws/lib/carrierwave/storage/aws_file.rb

Lines 98 to 108 in 09c5baa

	def url(options = {})
	if signer
	signed_url(options)
	elsif public?
	public_url
	else
	authenticated_url(options)
	end
	end

I found I could use asset_host_public configuration option to ensure the public? method returns true -- this is the desired result we needed. However, I couldn't find the documentation about this option in the README.md.

carrierwave-aws/lib/carrierwave/storage/aws_file.rb

Lines 122 to 126 in 09c5baa

	def public?
	uploader.aws_acl.to_s == 'public-read' || uploader.asset_host_public
	end

I can see it in the CHANGELOG.md where indicate this configuration option is fixed in Version 1.5.0 on 2020-04-01

Just checking, is this option just missed out from the documentation or is there any side-effect to use this "hidden" configuration?

Thanks
Peter