Add corresponding Ressources to each part and estimate how much time that takes to learn this

[kasali]

Add corresponding resources to each part and estimate how much time that takes to learn this from zero to hero.

For instance to learn kotlin :

• https://hyperskill.org/tracks/18
• https://kotlinlang.org/docs/home.html
• https://developer.android.com/kotlin
• https://www.udacity.com/course/kotlin-bootcamp-for-programmers--ud9011