KnowledgeAgentDefinitionParser can get NPEs

KnowledgeAgentDefinitionParser assumes that a spring bean definition has a bean class name, however when the bean extends a parent then it may not, as in the following example:

<bean id="freemarkerConfiguration" class="freemarker.template.Configuration">
</bean>

<bean id="workflowFreemarkerConfiguration" parent="freemarkerConfiguration">
<property name="templateLoader">
<bean class="au.com.core.messaging.freemarker.FreemarkerMessageLayoutTemplateLoader" />
</property>
</bean>

The BeanDefinition for bean "workflowFreemarkerConfiguration" has a null bean class name which causes KnowledgeAgentDefinitionParser.parseInternal to throw an NPE. Specifically this line:

if ( def.getBeanClassName().equals( StatelessKnowledgeSessionBeanFactory.class.getName() ) ) {