Layered lookups

[Jacques Le Roux]

Hi,

At r937852 I have commited changes for most lookups to be now layered. There are some exceptions: the lookups called from lookup are 
not layered.
If you find any issues please report here and we will see if it's necessary to create a Jira issue under 
https://issues.apache.org/jira/browse/OFBIZ-3445 for them

Thanks

Jacques