databases/cego: 2.26.12 -> 2.26.13

• Fix in CegoAttrDesc::evalReferences. In case of join objects, the refCount was not calculated correcty, since just the join object was analysed but not the sub content object. For this, a new method was introduced ( evalTableReferences ) and in case of join object, evalReferences is called recursive for all sub content objects

Submitted by: Bjoern Lemke <lemke@lemke-it.com>