use translatable descriptions for stadard and additional IEC function
blocks from xml files instead of hardcoded in python

move code in mki18n.py generated translation strings from custom files into separate function

clean search result panel after open another project

fix highlight of search result in Search Result Panel
Remove previous highlight, after next search result clicked.

fix doubling search results in Search Result Panel

After fix local search in SFC POU in 163d3a8, search results tree assemble with "children" branches: results of search in actions anf transitions. Deleted code doubling this search results into one more separate branch, so it's useless.

make FindInPouDialog work on Windows with wxPython 2.8

additional fix for changeset 474de7f

fix local search in actions and transitions

convert FindInPouDialog from wx.Frame to wx.Dialog

In this case FindInPouDialog Windows isn't listed in windows manager
on Alt-Tab. And it's not shown on top of other applications. For
example, previously the dialog was shown even on top of web browser or
word processor.

temporary disable SFC transitions in IL, because matiec can't compile it

matiec freezes in this case.
See https://bitbucket.org/mjsousa/matiec/issues/58/iec2c-freezes-if-sfc-transition-is-in-il

fix issue with creating SFC transitions using ST and IL

Beremiz generates text representation for transitions without names.
Therefore transition name in its IL code is not needed.