Scala Adaptor Details

With https://github.com/Netflix/RxJava/pull/503, some files were lost, so I added them again, and I also fixed many other details. There are no changes in functionality/inheritance, only "cosmetics". Except https://github.com/samuelgruetter/RxJava/commit/8567fcbaff20859c68ce4c30c7f347be34581fa4 : @headinthebox could you please confirm this one-line change?