Add domainName property and modify getName() to return full identifier

ACE-83
Modify constructor and add getFullIdentifier()

ACE-83
Add domainName property and modify getName() to return full identifier

ACE-83
Modify constructor and add getFullIdentifier()

ACE-83
Refactor UserNameTest to UserIdentifierTest

Add getDomain to UserIdentifier

ACE-83
Merge remote-tracking branch
'origin/RefactorUserNameToUserIdentifier_ACE-83' into
RefactorUserNameToUserIdentifier_ACE-83

Conflicts:
	org.ualerts.chat.service/src/main/java/org/ualerts/chat/service/api/UserIdentifier.java
	org.ualerts.chat.service/src/test/java/org/ualerts/chat/service/api/concrete/UserNameTest.java
Modify MockUserService to use UserIdentifier

ACE-83
Line 52, access DEFAULT_DOMAIN in a static way

ACE-83
Merge pull request #39 from ualerts-org/RefactorUserNameToUserIdentifier_ACE-83

Refactor user name to user identifier ace 83