This is needed because until we have modules and dependencies implemented in
our IDEA plugin, the whole project always is analyzed to highlight any file in
the project. This resulted in weird errors in different modules in Kotlin
project because two declarations were found for each built-in class: the one in
kotlin-runtime.jar and the one (totally unrelated) in the 'builtins' module
'builtins' will be used for platform-independent core built-in definitions,
'runtime.jvm' for things that should be present at runtime in order for Kotlin
code to execute correctly on JVM
ProgressionUtil goes to 'builtins' right now because progression iterators
depend on it, but should be rewritten to Kotlin later