WIP: refactoring authentication

src/main/java/caosdb/server/CaosAuthenticator.java

src/main/java/caosdb/server/CaosDBServer.java

...db/server/accessControl/AnonymousAuthenticationToken.java

...java/caosdb/server/accessControl/AuthenticationUtils.java

...a/caosdb/server/accessControl/CaosDBAuthorizingRealm.java

...osdb/server/accessControl/OneTimeAuthenticationToken.java

...n/java/caosdb/server/accessControl/OneTimeTokenRealm.java

src/main/java/caosdb/server/accessControl/Principal.java

...rver/accessControl/SelfValidatingAuthenticationToken.java

src/main/java/caosdb/server/accessControl/SessionToken.java

...n/java/caosdb/server/accessControl/SessionTokenRealm.java

src/main/java/caosdb/server/accessControl/UserSources.java

.../caosdb/server/resource/AbstractCaosDBServerResource.java

src/main/java/caosdb/server/resource/ScriptingResource.java

src/main/java/caosdb/server/utils/Utils.java

...test/java/caosdb/server/authentication/AuthTokenTest.java

...st/java/caosdb/server/resource/TestScriptingResource.java