Fixed refresh problem following 9c5f835b031e, 9622418ac28c, c67488bd8134 : force redraw only through EVT_PAINT event and use wxPaintDC, as described in wx documentation

Beremiz's user manual
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Contents:

.. toctree::
   :maxdepth: 2

   install
   start
   edit
   build
   connectors
   debug