SEC-449: Remoned unnecessary declaration of ContextMapper interface.

core/src/main/java/org/acegisecurity/ldap/DefaultInitialDirContextFactory.java

@@ -27,7 +27,6 @@ import org.springframework.context.support.MessageSourceAccessor;
 
 import org.springframework.util.Assert;
 import org.springframework.ldap.UncategorizedLdapException;
-import org.springframework.ldap.core.ContextSource;
 import org.springframework.ldap.core.support.DefaultDirObjectFactory;
 import org.springframework.dao.DataAccessException;