UserView refaktorisiert

...ain/java/unipotsdam/gf/exceptions/MysqlDownException.java

...ava/unipotsdam/gf/exceptions/RocketChatDownException.java

...tsdam/gf/exceptions/UserDoesNotExistInMysqlException.java

.../gf/exceptions/UserDoesNotExistInRocketChatException.java

.../unipotsdam/gf/exceptions/UserExistsInMysqlException.java

...otsdam/gf/exceptions/UserExistsInRocketChatException.java

...rc/main/java/unipotsdam/gf/interfaces/ICommunication.java

...f/modules/communication/service/CommunicationService.java

...sdam/gf/modules/communication/view/CommunicationView.java

.../main/java/unipotsdam/gf/modules/project/ProjectView.java

...en/src/main/java/unipotsdam/gf/modules/user/UserView.java

...in/java/unipotsdam/gf/process/ProjectCreationProcess.java

...schen/src/main/java/unipotsdam/gf/session/GFContexts.java

...schen/src/main/java/unipotsdam/gf/taglibs/ChatWindow.java

...n/src/test/java/unipotsdam/gf/core/database/UpdateDB.java

...dules/communication/service/CommunicationServiceTest.java

.../java/unipotsdam/gf/process/tasks/GroupPhaseTaskTest.java