Remove all deprecated jpox dependencies as we switched to datanucleus

From Bart:

"Didn't we switch to datanucleus? I still see a lot of references to
jpox in the trunk:

api/NOTICE.txt:35:This project includes JPOX (http://www.jpox.org)
distributed under the Apache
application/jetty-config/log4j.xml:53: <category additivity="false"
name="JPOX">
application/jetty-config/log4j.xml:58: <category additivity="false"
name="JPOX.Plugin">
application/NOTICE.txt:35:This project includes JPOX
(http://www.jpox.org) distributed under the Apache
engine/src/main/resources/plugin.xml:42: <valuegenerator
name="auid" class-name="org.jpox.store.poid.AUIDPoidGenerator"
unique="true" datastore="jcr"/>
engine/src/main/resources/plugin.xml:43: <valuegenerator
name="uuid-hex" class-name="org.jpox.store.poid.UUIDHexPoidGenerator"
unique="true" datastore="jcr"/>
engine/src/main/resources/plugin.xml:44: <valuegenerator
name="uuid-string"
class-name="org.jpox.store.poid.UUIDStringPoidGenerator" unique="true"
datastore="jcr"/>
engine/src/main/resources/plugin.xml:46: <extension
point="org.jpox.store_query_query">
engine/src/test/resources/log4j.xml:69: <category additivity="false"
name="org.jpox.util">
engine/src/test/resources/log4j.xml:74: <category additivity="false"
name="org.jpox">
jca/src/main/resources/log4j.xml:56: <category additivity="false"
name="org.jpox.util">
jca/src/main/resources/log4j.xml:61: <category additivity="false"
name="org.jpox">
NOTICE.txt:35:This project includes JPOX (http://www.jpox.org)
distributed under the Apache
pom.xml:299: <groupId>jpox</groupId>
pom.xml:300: <artifactId>jpox-testframework</artifactId>
test/src/test/resources/log4j.xml:69: <category additivity="false"
name="org.jpox.util">
test/src/test/resources/log4j.xml:74: <category additivity="false"
name="org.jpox">"