[rfc] don't show at all non-flashing progress bar?

[Alexander Belchenko]

I see in recent bzr.dev that progress bar is not flashing on fast
operations (I saw Aaron's message about disabling flashing progress bar
on first 1-2 seconds).

But nevertheless progress bar is exists as string of spaces. And this
garbage (of space strings + '\r's) is catched by my editor anyway. Can
progress bar don't print anything at all when it try to print spaces?

--
Alexander