Add unique column ids to every column

These are necessary for gwtorm to map the entity onto either the
Thrift or protobuf encoding schemes, for storage in a system that
uses that style of object data encoding.

Change-Id: I50053fbe9a6d8023a3e0cd0c56ba39b3af0da665
Signed-off-by: Shawn O. Pearce <sop@google.com>
29 files changed