Suggests to add the Kotlin runtime library to the classpath (it it doesn't exists) on the new Kotlin file creation.

 #KT-5559 Fixed
On eclipse startup suggests to add the Kotlin runtime library to all projects that don't have it configured.

 #KT-55?? Fixed

Conflicts:
	kotlin-eclipse-ui/src/org/jetbrains/kotlin/wizards/NewUnitWizard.java
Now the addKotlinRuntime method doesn't throw FileNotFoundException.
Suggests to add the Kotlin nature and the Kotlin builder to the project if it is necessary.

Minor: refactoring

 #KT-55?? Fixed