Went out and tried for the second time to record a screencast demoing
setting up syncing between two computers using just Jabber and a cloud
remote. I can't record this one at home, or viewers would think git-annex
was crazy slow, when it's just my dialup. ;) But once again I encountered
bugs, and so I found myself working on progress bars today, unexpectedly.

Seems there was confusion in different parts of the progress bar code
about whether an update contained the total number of bytes transferred, or
the delta of bytes transferred since the last update. One way this bug
showed up was progress bars that seemed to stick at 0% for a long time.
Happened for most special remotes, although not for rsync or git remotes.
In order to fix it comprehensively, I added a new BytesProcessed data type,
that is explicitly a total quantity of bytes, not a delta. And checked and
fixed all the places that used a delta as that type was knitted into
the code.

(Note that this doesn't necessarily fix every problem with progress bars.
Particularly, buffering can now cause progress bars to seem to run ahead
of transfers, reaching 100% when data is still being uploaded. Still,
they should be a lot better than before.)

I've just successfully run through the Jabber + Cloud remote setup process
again, and it seems to be working great now. Maybe I'll still get the
screencast recorded by the end of March.
