NOJIRA refactoring based on walkthrough discussion, renamed securitycontextutils...

NOJIRA refactoring based on walkthrough discussion, renamed securitycontextutils->authncontext, added utility method to retrieve tenant name
test: all service tests

M    authentication/service/src/main/java/org/collectionspace/authentication/AuthN.java
D    authentication/service/src/main/java/org/collectionspace/authentication/realm/CSpaceDbRealm.java
A    authentication/service/src/main/java/org/collectionspace/authentication/realm/db
A  + authentication/service/src/main/java/org/collectionspace/authentication/realm/db/CSpaceDbRealm.java
D    authentication/service/src/main/java/org/collectionspace/authentication/spring/SpringSecurityContextUtils.java
A  + authentication/service/src/main/java/org/collectionspace/authentication/spring/SpringAuthNContext.java
A    authentication/service/src/main/java/org/collectionspace/authentication/spi
A  + authentication/service/src/main/java/org/collectionspace/authentication/spi/AuthNContext.java
D    authentication/service/src/main/java/org/collectionspace/authentication/SecurityContextUtils.java
M    authentication/service/src/main/java/org/collectionspace/authentication/jaas/CSpaceJBossDBLoginModule.java