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= What is Entity Synchronization (EntitySync) and how to use it?
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== Introduction to Entity Synchronization

The general idea behind the Entity Sync stuff is to re-create transactions from a central database into one or
more other databases, each represented by a set of records in the EntitySync and related entities.

Though the Entity Sync mechanism can be used without the now deprecated POS, it was mostly destined to it. 
It works well on a reliable network (LAN), it's a bit harder on Internet (WAN) but nothing impossible...

The four fields (lastUpdatedStamp, lastUpdatedTxStamp, createdStamp, createdTxStamp) are added to each entity and 
automatically populated so that queries can be done on each entity to get all records created, updated, 
or removed in a certain transaction, and so that in time order those transactions can be reproduced remotely 
to get the data into the remote database in the proper order.

The no-auto-stamp attribute is used to tell the Entity Engine not to automatically add these stamp fields, 
and not to automatically set the stamps when creating and updating the entities. It's false by default. 
So by default these values will be automatically set, and when records are removed the primary key will be saved 
in the EntitySyncRemove entity's table so that the record can be removed in the remote database.