Effects: add test on (de)serialization of contracts

- Add ContractDescriptorRenderer
- Add option to dump function contracts in DescriptorRendererOptions
- Add parsing of LANGUAGE_VERSION directive in AbstractLoadJava
- Add tests on serialization-deserializaton identity of contracts

==========
Introduction of EffectSystem: 13/18

core/descriptors/src/org/jetbrains/kotlin/renderer/DescriptorRenderer.kt

@@ -222,6 +222,7 @@ interface DescriptorRendererOptions {
     var renderUnabbreviatedType: Boolean
     var includeAdditionalModifiers: Boolean
     var parameterNamesInFunctionalTypes: Boolean
+    var renderFunctionContracts: Boolean
 }
 
 object ExcludedTypeAnnotations {

core/descriptors/src/org/jetbrains/kotlin/renderer/DescriptorRendererOptionsImpl.kt

@@ -109,4 +109,6 @@ internal class DescriptorRendererOptionsImpl : DescriptorRendererOptions {
     override var includeAdditionalModifiers: Boolean by property(true)
 
     override var parameterNamesInFunctionalTypes: Boolean by property(true)
+
+    override var renderFunctionContracts: Boolean by property(false)
 }