Removed calling of XftFontClose from BC_WindowBase destructor

If I understand libXft sources correctly, Xft cares itself about
font closing durig XCloseDisplay. Removing XftFontClose fixes
a race between XftFontClose, XCloseDisplay and XftFontOpenXlfd.
Removed disabling of xft from BC_Resources::x_error_handler

X error may be triggered by other causes on both 32 and 64 bit computers
Should fix the unpredictable font change