pgsql: Include previous TLI in end-of-recovery and shutdown checkpoint

Include previous TLI in end-of-recovery and shutdown checkpoint records.

This isn't used for anything but a sanity check at the moment, but it could
be highly valuable for debugging purposes. It could also be used to recreate
timeline history by traversing WAL, which seems useful.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/7803e9327db3788f68d820c19f4081afb79edd12

Modified Files
--------------
src/backend/access/rmgrdesc/xlogdesc.c  |    7 +++--
src/backend/access/transam/xlog.c       |   36 ++++++++++++++++++++++++++++--
src/bin/pg_controldata/pg_controldata.c |    2 +
src/bin/pg_resetxlog/pg_resetxlog.c     |    4 +++
src/include/access/xlog_internal.h      |    3 +-
src/include/catalog/pg_control.h        |    4 ++-
6 files changed, 48 insertions(+), 8 deletions(-)