Remove unused files
Move to work on 2.9.0 release

Upgrade all org.codehaus.groovy dependencies to 
1.8.6
Move groovy 17 and groovy 16 to attic

remove groovy 17 from build scripts.
[maven-release-plugin] prepare release groovy-eclipse-compiler-2.8.0-01
[maven-release-plugin] prepare for next development iteration
[maven-release-plugin] prepare release groovy-eclipse-compiler-2.9.0-01