Quickfix for NOTHING_TO_OVERRIDE: change function signature to match one of super function's signatures.

This implements "Modify method parameters/return type to match one of method in super-classes." solution from https://docs.google.com/document/d/1b9I-7VUMq8As9gd4agU8hPIXrBauplG8_4vLK5Pv-zw/edit#heading=h.6g59oaej69hc

I hope this fixes all the issues abreslav mentioned in https://github.com/JetBrains/kotlin/pull/227 . Due to using descriptors overriding Java methods works. Support for generics is limited and still needs some work.