Implement leap-core in Kotlin

[TheReturnOfJan]

Bounty

Start rewriting leap-core in Kotlin and make sure it behaves the same as now when compiled to JavaScript and can also be used for purposes such as in https://github.com/leapdao/leap-core/issues/152 in a JVM environment.

Scope

• [x] Set up Kotlin repository/project
• [x] Include documentation for people unfamiliar with Kotlin on how to get started
• [x] Implement one component (input) - https://github.com/leapdao/leap-core/blob/master/lib/input.js in Kotlin
• [x] Implement the component tests in Kotlin
• [x] Create an (as automatic as possible) testing procedure which makes sure the new implementation behaves the same as the old one (compile to JS -> run old tests)

Deliverables

A new repository containing the partial Kotlin leap-core implementation.

Gain for the project

• Typed leap-core
• Ability to use leap-core in JVM environment (can integrate with WallETH for example)

Roles

bounty gardener: @TheReturnOfJan / 10% bounty worker: @TheReturnOfJan / 60% bounty reviewer: @MaxStalker / 30%

[TheReturnOfJan]

Implementation here: https://github.com/TheReturnOfJan/leapcore

[troggy]

via https://github.com/leapdao/leap-core.kt/pull/1