I think the class org.hibernate.ejb.Hibernat ePersistence is missing from your classpath. Add it to your pom.xml:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>3.6.10.Final</version>
</dependency>
Replace 3.6.10.Final with the appropriate version of Hibernate.