Added: possibility to clean old build generated files with optional checkbox into job configuration form
Modified: jenkins version number into pom.xml file
Refactored to conform Gregory's remarks - use of FilePath.deleteRecursive()
Merge remote-tracking branch 'origin/master'

Conflicts:
	src/main/java/com/thalesgroup/hudson/plugins/tusarnotifier/TusarNotifier.java
	src/main/java/org/jenkinsci/plugins/dtkit/DTKitBuilder.java
Merge pull request #2 from bidulechou/master

Added clean old build generated files possibility