change white background for project tree element to transparent

because on GNU/Linux project tree has grey background, therefore
white background looks not good.

fix second error message in case of error appearing too early to have a wx frame

fix a side effect of 95ecb26fdc4e

remove old unused .cvsignore

fix issue with printing scheme (FBD, LD or SFC) with comment element on GNU/Linux

If you draw FBD scheme and place comment on it and then try to print
it, then no wires will be printed and comment box is empty (text is
missing). This happens only for wx.PrinterDC and not on wx.MemoryDC
that is used to draw print preview window in Beremiz IDE.
Looks like a bug in wxPython or wxWidgets.

There were found several workaround for this issue.
1) If some dc.DrawLines call is placed before dc.DrawPolygon, then the
problem is gone.

...
dc.DrawLines(polygon)
dc.DrawPolygon(polygon)
...

2) Reseting DC brush solves the problem as well (see this changeset).

detect iec2c options and ieclib path only once during the first build

attach checkedBlockDict variable to the body object

fix file header in AboutDialog.py

update Russian translation

check before program generation whether SFC step, that is referenced
by SFC jump, does exists

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