[FIX] setup: wkhtmltopdf win32 download location has moved

Wkhtmltopdf has moved from Sourceforge to download.gna.org.
See https://groups.google.com/forum/#!msg/wkhtmltopdf-general/wZwTUol3mXI/GNVeyrKDdqIJ

Fixes #7574
Closes #7578

setup/win32/static/getfiles.sh

@@ -13,7 +13,7 @@ trap cleanup EXIT
 wget -q http://get.enterprisedb.com/postgresql/postgresql-9.3.5-1-windows.exe
 
 # wkhtmltopdf
-wget -q -P $TEMPDIR http://downloads.sourceforge.net/project/wkhtmltopdf/0.12.1/wkhtmltox-0.12.1.2_msvc2013-win32.exe
+wget -q -P $TEMPDIR http://download.gna.org/wkhtmltopdf/0.12/0.12.1/wkhtmltox-0.12.1.2_msvc2013-win32.exe
 7z x -o$TEMPDIR $TEMPDIR/wkhtmltox-0.12.1.2_msvc2013-win32.exe
 cp $TEMPDIR/bin/wkhtmltopdf.exe ./wkhtmltopdf