implement new detector to find too long name of schema object.

Oracle database cannot support schema object which has name longer than 31 bytes. To find problem quickly, these detector will parse Entity class and report.

Note that current implementation cannot consider [NamingStrategy](http://docs.jboss.org/hibernate/core/3.3/reference/en/html/session-configuration.html#configuration-namingstrategy) and similar system to change naming strategy.