Added files for sbt 0.13,2,5,6

Updated 0.13.1/plugins/eclipse-plugin.sbt to 2.5.0

Copied the 0.13.1 files to 0.13.2, 0.13.5, and 0.13.6
Merge pull request #6 from jkleckner/update-sbt-13.2_5_6

Added files for sbt 0.13,2,5,6