improved Sonar plugin defaults

- don't pass non-existing directories (otherwise sonar-runner will complain)
- more accurate defaults for binaryDirs and libraries
reverted some changes to ModelToPropertiesConverter that weren't strictly necessary
adapted test to plugin changes
Sonar model enhancements

- added annotations for property conversion
- changed some property types from List/FileCollection to Collection
- added two new properties
switched from sonar-batch(-bootstrapper) API to sonar-runner API

- necessary to support Sonar 3.4 and higher
updated sonar smoke test to use sonar 3.4