Update config.h.win32.in

Make its entries match those that are checked by autotools in config.h.in
Add style classes to headerbar titles

The current theme just makes all text bold that appears anywhere
in a headerbar, which is not great. We add 'title' and 'subtitle'
style classes to allow more targeted overriding of the font.
Bug 705750 Quartz input method doesn't work correctly for Chinese characters

Modified from original for Gtk3.