Merge remote-tracking branch 'origin/development_master' into development_master

# Conflicts:
#	gemeinsamforschen/src/main/java/unipotsdam/gf/modules/project/ProjectDAO.java
#	gemeinsamforschen/src/main/java/unipotsdam/gf/process/tasks/Task.java
#	gemeinsamforschen/src/main/java/unipotsdam/gf/process/tasks/TaskDAO.java
#	gemeinsamforschen/src/test/java/unipotsdam/gf/process/tasks/GroupPhaseTaskTest.java