Remove hidden file handling

[Stebalien]

We should be able to handle this at the cmds (and maybe files) layer and filter hidden files out before they ever reach the CoreAPI. Does this make sense?

[magik6k]

It should be possible to implement this as a proxy files layer, that would make things much nicer in the adder code.

(also, with the current way it works, we send hidden files to the daemon, just so they get dropped there)

[Stebalien]

Are you sure we send hidden files? It looks like the commands library is dropping them, as far as I can tell.

[magik6k]

It looks like the commands library is dropping them

Right, we do that (with a small bug - ipfs/go-ipfs-files#11), and it makes things much simpler if we don't care about handling hidden in http api - I removed all hidden file handling from CoreAPI and the command in
ipfs/kubo#6019, and it still just works.

(If we want to remove hidden handling from http api, we'll probably need to adjust what js-ipfs does)

[Stebalien]

js-ipfs does it client-side as well.

[magik6k]

ipfs/kubo#6019