Added a .gitignore file
Added a .gitignore file

To exclude .class files and target directory

charybdeBE/Cytomine-core,cytomine/Cytomine-core,charybdeBE/Cytomine-core,cytomine/Cytomine-core,cytomine/Cytomine-core,charybdeBE/Cytomine-core,charybdeBE/Cytomine-core,charybdeBE/Cytomine-core,charybdeBE/Cytomine-core,charybdeBE/Cytomine-core,cytomine/Cytomine-core,cytomine/Cytomine-core,cytomine/Cytomine-core,charybdeBE/Cytomine-core,charybdeBE/Cytomine-core,charybdeBE/Cytomine-core