Kotlin

Add Kotlin Spring compiler plugin to module build  

Adds Spring Kotlin compiler plugin to project build files:.

Java-style call with Kotlin extension alternative  

Reports places where a Kotlin Spring extension can be used instead of a call with a ::class.java argument.

Remove redundant open modifier  

Reports usages of open modifier for Spring framework classes.

Spring Kotlin router DSL  

Reports unused path variables in Kotlin router DSL as well as usages of undeclared path variables.