Don't hardcode activities-tabs-face foreground about activities.el

[alphapapa]

Hi Karthik,

Thanks for the kind words. I'm glad it's useful to you.

I understand the problem with theming, and I'd be glad to define the face in a better way, but since face inheritance is all-or-nothing, this was the best I could come up with to inherit just the foreground color.

But I do see that, e.g. with Prot's ef-themes and with the default Emacs theme, the font-lock-function-name-face only defines a foreground color, so I guess we can just inherit from it and hope that if other themes change it in other ways, it will turn out okay. (And if not, the user can still customize it to fix it.)

I'll fix this in the next version. Thanks for mentioning it.