introduced UserCredentials parameter object, added
PostLoginProcessContext
finished UserCredential refactoring, UserPassword doesn't exist anymore,
tests adapted and working
Merge branch 'process-context'

Conflicts:
	org.hive2hive.core.test/src/org/hive2hive/core/test/process/common/GetUserProfileStepTest.java
	org.hive2hive.core.test/src/org/hive2hive/core/test/process/common/PutUserProfileStepTest.java
	org.hive2hive.core/src/org/hive2hive/core/process/login/ContactPeersStep.java