[JCENTER] Update dependencies and configuration

[thiago-you]

Hi, how you guys doing?

I ported this library with updated dependencies and configurations, also moved out from JCenter do use Jitpack.io:

https://github.com/thiago-you/material-spinner

• Move from JCenter to Jitpack.io
• Migrate do Androidx libraries
• Drop jetifier support
• Update dependencies and libraries
• Update configurations
• Kotlin compatibility

Check it out!