Converting spring-based ldap components over to ldaptive
Ldap svc registry based on ldaptive.
Ldap svc registry based on ldaptive. added test case.
Merge pull request #268 from serac/credentials

Credential refactoring, Credentials -> Credential, for code clarity and adherence to vocabulary of NIST 800-63.
Merge branch 'feature-new-authn-api' into SPNG-LDAP-REMOVAL

Conflicts:
	cas-server-support-ldap/src/main/java/org/jasig/cas/adaptors/ldap/BindLdapAuthenticationHandler.java
	cas-server-support-ldap/src/main/java/org/jasig/cas/adaptors/ldap/FastBindLdapAuthenticationHandler.java
	cas-server-support-ldap/src/main/java/org/jasig/cas/adaptors/ldap/remote/RemoteIpLookupCredentialsToPrincipalResolver.java
	cas-server-support-ldap/src/main/java/org/jasig/cas/authentication/principal/CredentialsToLDAPAttributePrincipalResolver.java
	cas-server-support-ldap/src/test/java/org/jasig/cas/adaptors/ldap/BindLdapAuthenticationHandlerTests.java
	cas-server-support-ldap/src/test/java/org/jasig/cas/adaptors/ldap/FastBindLdapAuthenticationHandlerTests.java
	cas-server-support-ldap/src/test/java/org/jasig/cas/authentication/principal/CredentialsToLDAPAttributePrincipalResolverTests.java
Addressing code reviews, new reg svc id, switched to arraylist and added required reg svc prop for authn handlers.
Updated tests on required handlers.
Ldap credential resolver changes that delegates to an inner resolver for constructing principal out of the request.

Added minor improvements to ease the definition of search queries based on uid attr providers of person directory.
Cleaned up bean definitions to be able to properly run unit tests.
Merge pull request #269 from mmoayyed/SPNG-LDAP-REMOVAL

Ldaptive-based LdapServiceRegistry implementation and test cases. 

Also, remove all spring-ldap related classes and adjust all based on ldaptive.
Merge branch 'feature-new-authn-api' into LDAP-CRED-RESOLVER
Merge pull request #270 from serac/port-handlers

Port authentication handlers to new AuthenticationHandler interface.
Credentials to Ldap Principal Resolver: Remove dependency to Person Directory's IUsernameAttributeProvider
Merge pull request #271 from mmoayyed/LDAP-CRED-RESOLVER

Ldaptive-based CredentialsToLdapPrincialResolver implementation
CAS-1238 Refactor principal resolver components.

1. Rename CredentialToPrincipalResolver -> PrincipalResolver.
2. Leverage symmetry between Credential and Principal ID to create a
   generic principal resolution strategy, BasicPrincipalResolver.
3. Make Person Directory resolver a concrete class that uses generic
   principal ID resolution strategy by default and add capability to set
   principal ID with an attribute value from Person Directory query results.
4. Delete deprecated and superfluous resolver components.
5. Rename some X.509 resolver components for clarity/consistency.
Fix bugs introduced by default registered service ID change.
CAS-1238 LDAP component tweaks following rebase.

Mostly checkstyle fixes and some name changes related to PrincipalResolver
rename.