[OCM] ocm cache

[Padraic Hannon]

There is a simple OCM cache which I would like to remove or at least  
make optional. Currently there is already a lot of caching going on  
within jackrabbit and the current cache implementation for OCM is  
extremely simplistic. For example, if a node changes under the OCM it  
has no knowledge of this and the cache is not flushed. Until there is  
robust support for observation and a more plug-able architecture the  
OCM cache seems like it is more dangerous than helpful.

WDYT?
paddy