server add update method to abstract class implementation
server improve updates
Merge branch 'dev'

Conflicts:
	server/src/at/ac/uibk/informatrix/ride4earth/global/classes/AbstractCredit.java
	server/src/at/ac/uibk/informatrix/ride4earth/global/classes/AbstractRide.java
	server/src/at/ac/uibk/informatrix/ride4earth/logic/business/entities/CommunityUserImpl.java