Results 3 issues of heckej

This will add the ability to ProGuard to apply an optimisation called _lambda merging_ which combines the implementations of multiple Kotlin lambda classes in a common class, called a lambda...

This will add visitors that are used to implement lambda merging in ProGuard (see pull request for ProGuard: [Implementation of lambda merging for Kotlin lambda classes #257](https://github.com/Guardsquare/proguard/pull/257)).

# Problem When the option `font` exists (either by setting the option in an `mdframed` environment or by setting it as a document option), the value of this option is...