#369 - Add Kotlin property and plugin to build parent.

[christophstrobl]

resolves #369

[odrotbohm]

I'm kind of wondering what the implications of this are for projects that don't add any Kotlin extensions currently. Do they still compile as expected? Does the IDE setup create issues?

[christophstrobl]

@olivergierke everything seems to work just fine even after adding the plugin. The step is just skipped when there's no src/main/kotlin directory available. Maybe @sdeleuze can have a look at this one as well.

[sdeleuze]

Even if the syntax is verbose, this is to me the right way to support mixed Kotlin + Java project with maven indeed and that should not cause any issue in IDEs (already widely used by a lot of developers). In case we detect something, Kotlin team is quite responsive to our issue reports.