Support file uri scheme

[phanirithvij]

curl supports file:// scheme.
wget doesn't.

Would be nice to have it so that fuse can be utilised for some operations as a secondary source.

I have an example use case where an android filesystem can be mounted using https://github.com/whoozle/android-file-transfer-linux and an http server can be utilised as well, combined together can result in faster transfer.