Major refactoring of the occurances NEED TESTING

...a/be/uantwerpen/datamining/pattern_mining/ArffToSPMF.java

...pen/datamining/pattern_mining/MakePatternOccurrences.java

...datamining/pattern_mining/MakePatternOccurrencesSpan.java

...e/uantwerpen/datamining/pattern_mining/MineUsingSPMF.java

.../be/uantwerpen/ldataminining/preprocessing/ArffUtils.java

src/main/java/be/uantwerpen/ldataminining/utils/IOUtils.java

...uantwerpen/mime_webapp/controller/AbstractController.java

...rpen/mime_webapp/controller/DataManagementController.java

...erpen/mime_webapp/controller/PatternMiningController.java

...antwerpen/mime_webapp/controller/TransformController.java

...java/be/uantwerpen/mime_webapp/dao/ProjectRepository.java

src/main/java/be/uantwerpen/mime_webapp/model/FileItem.java