Identity column and sequence numbers support. Added support for IDENTITY columns. Finished sequence numbers functionality. Bug fixes and perf enhancements in those areas. This code has been pre-reviewed by Joanie C.
added support for externalized Sequence numbers. -- sql statements: create/drop/alter/get/showddl sequence for sequence objects -- function 'seqnum' to retrieve sequence numbers. An external spec has been created. Launchpad #1349985 Code reviewd by Joanie C, Suresh S, Selva and Sandhya. Full dev regressions run and passed.