Minor refactor of FuncTestCase::tearDownTestProject
Minor refactor of FuncTestCase::tearDownTestProject

- use existing FS service
- check project dir exists before removal

bangpound/sculpin,sculpin/sculpin,davereid/sculpin,thomas-p-wilson/sculpin,sculpin/sculpin,vrkansagara/sculpin,opengbu/sculpin,beryllium/sculpin,steveleec/sculpin,opdavies/sculpin,beryllium/sculpin,cyberid41/sculpin,brianjking/sculpin,carbontwelve/sculpin,MalangPHP/sculpin,lury/sculpin