Add support for Java 8

SCHWERWIEGEND: Exception sending context initialized event to listener instance of class com.atlassian.bamboo.ww2.actions.setup.BambooContextLoaderListener
org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from class path resource [applicationContextManagers.xml]; nested exception is java.lang.IllegalStateException: AnnotationAwareAspectJAutoProxyCreator is only available on Java 1.5 and higher
Caused by: java.lang.IllegalStateException: AnnotationAwareAspectJAutoProxyCreator is only available on Java 1.5 and higher
	at org.springframework.aop.config.AopNamespaceUtils.getAspectJAutoProxyCreatorClassIfPossible(AopNamespaceUtils.java:145)
	at org.springframework.aop.config.AopNamespaceUtils.registerAtAspectJAutoProxyCreatorIfNecessary(AopNamespaceUtils.java:95)
	at org.springframework.aop.config.AspectJAutoProxyBeanDefinitionParser.parse(AspectJAutoProxyBeanDefinitionParser.java:41)
	at org.springframework.beans.factory.xml.NamespaceHandlerSupport.parse(NamespaceHandlerSupport.java:69)
	at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1123)
	at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1113)