feat: add activeFontStyle prop

[Naturalclar]

Overview

• removed textColor and activeTextColor props
• added color attribute in fontStyle prop
• Added an activeFontStyle props which contains color, fontSize, and fontFamily for active State
• added a default color for selected segment, so the tint color won't cover the text when no text color is set.
• added fontFamily support for android and web

Test Plan

Tested on iOS/Android simulator

[Naturalclar]

@arjndr @kesha-antonov
I've changed up the props a bit from #87 and simplified the props a bit. What do you think?

Now theres a fontStyle prop that can take color, fontWeight, and fontSize,
and if you want a separate style for selected segment, you can also use activeFontStyle to override the fontStyle for selected segment.

If you have any suggestions, let me know.

[arjndr]

Way better! Easier to understand too, +1 on this

[kesha-antonov]

@Naturalclar thanks!