Feature request: Cache Driver

[daniel-samson]

Is your feature request related to a problem? Please describe.

I want to be able to cache files to the local filesystem when using drivers like s3, ftp, and http. This is useful when retrieving files that do not frequently change but are hosted over the network wire.

Describe the solution you'd like

I should be able to set the driver to 'cache' and then set the 'actualDriver' to 's3'. The cache driver should cache files and their respective changes.

Describe alternatives you've considered

Additional context