Fail to build from source

When building from source, I first get syntax errors (fixed via the attached patch), and then I get a build failure, in which the error messages are:


~~~
* Exception is:
java.lang.NoClassDefFoundError: kotlin/jvm/internal/Intrinsics
        at com.install4j.gradle.Install4jPlugin.apply(Install4jPlugin.kt)
        at com.install4j.gradle.Install4jPlugin.apply(Install4jPlugin.kt:6)
        at org.gradle.api.internal.plugins.ImperativeOnlyPluginTarget.applyImperative(ImperativeOnlyPluginTarget.java:42)
        at org.gradle.api.internal.plugins.RuleBasedPluginTarget.applyImperative(RuleBasedPluginTarget.java:50)
        at org.gradle.api.internal.plugins.DefaultPluginManager.addPlugin(DefaultPluginManager.java:165)
        at org.gradle.api.internal.plugins.DefaultPluginManager.access$200(DefaultPluginManager.java:47)
~~~

The problem is still present in the current git commit: d5bd34eb49f43735e240058f8875ab0bfcae4441

My system: Ubuntu, but I get the same error with a recent Debian (testing).

Thanks