Upgrade Babel sample (WPF & Android)

[PoLaKoSz]

Thank You for this great library!

Although I have read the Don't "Push" Your Pull Requests I could not find any example in this repo how to make this code review more easy because I upgraded the project from 4.0.0-beta8 to 6.2.3 .

📓 Notes

• upgraded Android
  • minSDK to 19
  • targetSDK to 19
• I could not upgrade these:
  • Babel.Ios
  • Babel.Phone
  • Babel.Store

Reference #122

[dnfclas]

All CLA requirements met.