autopep8 -i --select=W602
Also some other minor deprecated syntax changes, like "while 1".
I did not commit the less obvious changes.

refs #806

Remove useless trailing \
Remove trailing spaces
Add missing empty lines

autopep8 -ir -j2 --select=E301,E302,E502,W291,W293,W391 .

Diff quickly checked.

So no need for this check anymore.

refs #774 and reverts a change of 9c5326c0

Collections are not stored in replapplication.objects anymore, but in
replapplication.collections. This fixes the IDs issue. There was no gain
from storing them in objects.

Completion right after cd should be faster (and should always have been
like that, it was pretty much a bug).

The display of do_ls() should be much clearer. Collections are always at
the end, have ids/title/backend like objects (but using a formatter
would be better than my current hack).

There are still many issues with the current implementation.
refs #774
closes #785

correctly handle BrowserUnavailable and BrowserIncorrectPassword exceptions in repl applications (closes #302)

It asks user to reconfigure backend when BrowserIncorrectPassword is
raised.