Update debian/changelog

Update to 20130913 (commit: aebf7461)
Fix previous malformed changelog

Change-Id: Ib6ce94c157955181a2a80b9459d3264a31d2983a
Remove scala 2.8 annotations

They conflict with 2.9+ ones since they are basically duplicates used by
sbt

Change-Id: I3ba2adfacf9dc5dd2d0f47ee53f4c9c91bc74f4c