Allow caches to be evicted separately (per cacheable target). Renamed cache file name to fix issues when the target name contains path separators.


git-svn-id: http://sbuild.tototec.de/svn/sbuild/trunk@470 024a02f7-42f7-40fc-9f58-65666d1f2450
Added project for plugins.


git-svn-id: http://sbuild.tototec.de/svn/sbuild/trunk@471 024a02f7-42f7-40fc-9f58-65666d1f2450