Avoid dictionary initialization during import in PouDialog

Because initialization happened before i18n setup, then it causes later
problems during creating new POU on non-English locales (Russian for example).

Traceback (most recent call last):
File "/home/developer/WorkData/PLC/beremiz/beremiz/IDEFrame.py", line 2332, in OnAddPouMenu
dialog = PouDialog(self, pou_type, type_readonly)
File "/home/developer/WorkData/PLC/beremiz/beremiz/dialogs/PouDialog.py", line 101, in __init__
self.RefreshLanguage()
File "/home/developer/WorkData/PLC/beremiz/beremiz/dialogs/PouDialog.py", line 154, in RefreshLanguage
if language != "SFC" or PouDialog.POU_TYPES_DICT[self.PouType.GetStringSelection()] != "function":
KeyError: u'\u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u0430'

#EDE (Engineering-Data-Exchange) - generated by Beremiz BACnet plugin;;;;;;;;;;;;;;;
PROJECT_NAME;%(Project Name)s;;;;;;;;;;;;;;
VERSION_OF_REFERENCEFILE;%(EDE file version)d;;;;;;;;;;;;;;
TIMESTAMP_OF_LAST_CHANGE;%(Current Time)s;;;;;;;;;;;;;;
AUTHOR_OF_LAST_CHANGE;%(Project Author)s;;;;;;;;;;;;;;
VERSION_OF_LAYOUT;2.1;;;;;;;;;;;;;;
#mandatory;mandatory;mandatory;mandatory;mandatory;optional;optional;optional;optional;optional;optional;optional;optional;optional;optional;optional
#keyname;device obj.-instance;object-name;object-type;object-instance;description;present-value-default;min-present-value;max-present-value;settable;supports COV;hi-limit;low-limit;state-text-reference;unit-code;vendor-specific-address