EJB3 Entity Cache Metrics

These statistics must be reflected in the admin-console/Jopr.

Split from JBAS-6624:

EJB3 Entity Tree Cache (in addition to availability)
<!-jboss.cache:service=EJB3EntityTreeCache->
<metric property="NumberOfLocksHeld" displayType="summary"/>
<metric property="NumberOfNodes" displayType="summary"/>

EJB3 Entity Tree Cache Interceptor (in addition to availability)
<!-jboss.cache:service=EJB3EntityTreeCache,treecache-interceptor=CacheMgmtInterceptor->
<metric property="HitMissRatio" displayType="summary" units="percentage"
description="Returns the hit/miss ratio for the cache. This ratio is defined as hits/(hits + misses)."/>
<metric property="ReadWriteRatio" displayType="summary" units="percentage"
description="Returns the read/write ratio for the cache. This ratio is defined as (hits + misses)/stores."/>
<metric property="Hits" displayType="summary"/>
<metric property="Misses" displayType="summary"/>
<metric property="Evictions" displayType="summary"/>
<metric property="NumberOfLocksHeld"/>
<metric property="NumberOfNodes"/>
<metric property="AverageWriteTime" units="milliseconds"/>
<metric property="TimeSinceReset" units="seconds"/>
<metric property="AverageReadTime" units="milliseconds"/>
<metric property="NumberOfNodes"/>
<metric property="Stores"/>
<metric property="NumberOfAttributes"/>
<metric property="ElapsedTime" units="milliseconds"/>