Consider official GDG font for titles in the apps

[tasomaniac]

Last year Google rebranded and slightly changes GDG logo and chapter logos. Now chapters mostly use Google Product Sans.

It is not generally ok to use that font for everything but I think we can seriously consider using that for titles. I think that would look awesome.

[PareshMayani]

Why not also for Logo?

[tasomaniac]

Of course. That should be changed as well. That is tracked in #525