Fix missing RsDiscPgpKeyItem initialization
Fix inconsistent new[]/delete[] usage in RsDiscPgpKeyItem and
PGPHandler::exportPublicKey which now consistently uses malloc/free
Remove deprecated RsGenericSerializer::FORMAT_*
Move from deprecated RsServiceSerializer::SERIALIZATION_FLAG_* to
RsSerializationFlags
Solve a bunch of compiler warnings
Stricter checks in SerializeContext costructor