implementing groupTasks. Not quiet done yet

.../modules/group/preferences/groupal/JacksonPojoToJson.java

...gf/modules/group/preferences/groupal/PGroupAlMatcher.java

...f/modules/submission/controller/SubmissionController.java

...nipotsdam/gf/modules/submission/model/FullSubmission.java

...f/modules/submission/model/FullSubmissionPostRequest.java

...potsdam/gf/modules/submission/view/SubmissionService.java

...in/java/unipotsdam/gf/process/DossierCreationProcess.java

...ain/java/unipotsdam/gf/process/PeerAssessmentProcess.java

...va/unipotsdam/gf/process/tasks/GroupFeedbackTaskData.java

...schen/src/main/java/unipotsdam/gf/process/tasks/Task.java

...en/src/main/java/unipotsdam/gf/process/tasks/TaskDAO.java

gemeinsamforschen/src/main/webapp/project/create-project.jsp

gemeinsamforschen/src/main/webapp/project/tasks-docent.jsp

...rc/test/java/unipotsdam/gf/modules/group/GroupAlTest.java

gemeinsamforschen/src/test/resources/database/fltrail.sql