TPTools+AthenaPoolCnvSvc: Add class for writing a thinned vector.
Add TPThinnedPtrVectorCnv, which is like TPPtrVectorCnvConst except that it applies (MT) thinning during writing.
Add support for passing SG key through top-level TP converter.
Add TPThinnedPtrVectorCnv, which is like TPPtrVectorCnvConst except that it applies (MT) thinning during writing.
Edited by Scott Snyder