Rsync support

[kfogel]

@danfuzz mentioned that rsync access would be even better than SFTP access, at least for some use cases. After some internal discussion, we agreed that this tracker is the appropriate place to file this, even though if rsync support is ever implemented it would probably done as a new service.

CC @cecilia-donnelly @slifty @fenn-cs @jasonaowen

[slifty]

Just wanted to document my thoughts while I'm here in case it's useful!

This is a cool idea but I agree it is bigger in scope than the "enhancement" might imply. I think this idea would amount to an entire multi-quarter development project in itself.

As I understand it, rsync is an entirely different protocol from sftp, and would involve a different service. That effort would ideally also involve spinning out the concept of a "permanent file system" into a library that could be accessed by both services.

I defer to the permanent team as to whether or not they would like to keep this issue open in the mean time. I'd suggest that if this isn't likely to be taken on in the next few years it might make sense to mark it as a wontfix and move the concept to a higher level location that is used by Permanent for long term road map planning.