Fallback to username/password auth in jobviewer

fix translation in troubleshoot menu

FIX: spelling error

Removing zdohnal from links

Use remote server ppd file, in case a printer has been shared via cups

Remove more uses of deprecated GObject.SIGNAL_RUN_LAST

convert ppds.normalize comments to doc-string

9ae2308a removed many of these but these
two were left over.

Fix problems with saving of advanced settings

in python3 os.read returns byte object not a string which caused
writing loop to be endless

by adding b'' comparison we hold compatibility both with python2
and python3

After reading from stream we must return again to line 0 if we
want to read file again

Fix troubleshoot

- os.stat call expects file path not file object

- If dbus method is called with empty array as an argument then
dbus is not able to determine type of arguments and throws Error
- This commit adds way how to add it in such case

- until now timestamp was accessible only after some conditions
were met which resulted in occasional bug

dbus: remove deprecated at_console statement