Most remotes have meters in their implementations of retrieveKeyFile
already. Simply hooking these up to the transfer log makes that information
available. Easy peasy.
This is particularly valuable information for encrypted remotes, which
otherwise bypass the assistant's polling of temp files, and so don't have
good progress bars yet.
Still some work to do here (see progressbars.mdwn changes), but this
is entirely an improvement from the lack of progress bars for encrypted
downloads.
Easy!
Note that with an encrypted remote, rsync will be sending a little more
data than the key size, so displayed progress may get to 100% slightly
quicker than it should. I doubt this is a big enough effect to worry about.
