fix problem running PLCOpenEditor

$ ./PLCOpenEditor.py
../src/common/stdpbase.cpp(62): assert "traits" failed in Get(): create wxApp before calling this

Regression was introduced by '3311eea' (clean-up: fix PEP8 E402 module level import not at top of file)

<?xml version="1.0" encoding="UTF-8"?>
<BeremizRoot URI_location="LOCAL://">
  <TargetType/>
</BeremizRoot>