fix missing root in empty search results panel

add possibility to specify subprocess stdout encoding

fix deadlock if method kill() is called after process is already finished

fix pylint py3k conversion warning: "(no-absolute-import) import missing `from __future__ import absolute_import`"

make CanFestival to be at the expected place in bitbucket pipelines container

fix pylint error '(unsubscriptable-object) Value 'X' is unsubscriptable'

fix pylint warning '(bad-continuation) Wrong hanging indentation before block'

force all python source code to have LF line ending

fix pylint warning '(expression-not-assigned) Expression "X" is assigned to nothing'

fix pylint warning '(redefine-in-handler) Redefining name 'X' from outer scope (line Y) in exception handler'

fix displaying result of update check during Beremiz startup

fix pylint warning '(no-init) Class has no __init__ method'

fix pylint error "(undefined-variable) Undefined variable 'X'"

fix problem happend when tests are running under python-coverage

$ python-coverage run ./tests/tools/test_application.py

Exception while connecting LOCAL://!
Traceback (most recent call last):
File "/home/developer/WorkData/PLC/beremiz/beremiz/ProjectController.py", line 1753, in _Connect
self._SetConnector(connectors.ConnectorFactory(uri, self)
File "/home/developer/WorkData/PLC/beremiz/beremiz/ProjectController.py", line 1702, in _SetConnector
if connector is not None:
PyAssertionError: C++ assertion "m_window" failed at ../src/gtk/dcclient.cpp(2043) in DoGetSize(): GetSize() doesn't work without window