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

fix pylint error '(too-many-function-args) Too many positional arguments for function call'

fix pylint error '(import-error) Unable to import X'

fix pylint error '(no-self-argument) Method should have "self" as first argument'

fix pylint error "(no-name-in-module) No name 'X' in module 'Y'"

fix pylint error '(bad-except-order) Bad except clauses order (X is an ancestor class of Y)'

fix pylint warning "(no-value-for-parameter) No value for argument 'X' in function call"

fix problems with unconnected input of InOut function variables and
enfoce InOut variables to be connected for functions and function blocks

fix error for functions with VAR_IN_OUT

The problem was found by pylint '(used-before-assignment) Using variable "X" before assignment'

fix pylint warning '(unidiomatic-typecheck) Using type() instead of isinstance() for a typecheck'

fix pylint warning '(misplaced-bare-raise) The raise statement is not inside an except clause'