HSQLDB upgrade to 2.2.8
Set extended persistence context explicitly
Merge branch 'master' into jpa-dev
JPA: Initialize m_factoryTable outside init() method.

This allows methods getFactory(String) and createEntityManager(String)
methods to be useful even in case OpenCms installation doesn't use JPA
layer. For example OpenCms can use MySql driver with module which uses
JPA.
Merge pull request #57 from goshoo/jpa-dev

Some updates regarding JPA persistence and HSQLDB.