Font issue on Macos Catalina Dark Appearance

[ericmoret]

When running the gui I receive an error message as seen below. Note that this does not seem to have consequences when macos is configured in light mode, however in dark mode the non selected UI controls are displaying empty, see attached screenshot.

% pdf2pdfocr_gui.py
2020-04-11 08:16:46.702 Python[45232:697646] CoreText note: Client requested name ".SFNS-Regular", it will get Times-Roman rather than the intended font. All system UI font access should be through proper APIs such as CTFontCreateUIFontForLanguage() or +[NSFont systemFontOfSize:].
2020-04-11 08:16:46.702 Python[45232:697646] CoreText note: Set a breakpoint on CTFontLogSystemFontNameRequest to debug.

[LeoFCardoso]

Thank you. I never use dark mode on my Mac. I'll submit a issue to Gooey project and keep this open.

[LeoFCardoso]

Last commit fixes colors in GUI. It's not perfect, but better. Please try.