Add CircularRangeSlider

[diegotid]

• Project Name: Circular Range Slider
• Project URL: https://github.com/diegotid/circular-range-slider
• Project Description: A customizable SwiftUI component for selecting a range of values using a circular slider
• Why it should be added to awesome-swift: It is a fancy UI control which we devs want to mimic from the iOS Wake Up feature, and it is 100% SwiftUI, customizable and easy to use. No stars so far because I just open-sourced it today (I originally developed it as a component of a personal application of my own)
• At least 15 stars (GitHub project)
• Support Swift 5
• Updated contents.json instead of README
• Lib is fully open sourced, written in Swift and not a wrapper over compiled lib
• Description does not say "written in Swift" or variant 🤓