Add TAP tests for client programs

Reviewed-by: Pavel Stěhule <pavel.stehule@gmail.com>
Reviewed-by: Erik Rijkers <er@xs4all.nl>
Add @configure_input@ marker to Makefile.global.in

That way, when looking at Makefile.global, we don't get confused by the
comment that claims that this is Makefile.global.in.
Have lcov call the right gcov

By default, lcov will call whatever gcov it can find in the path.  But
if the user has specified a different gcov to configure, this could be
incompatible.  So tell lcov explicitly with an option which gcov program
to call.
vacuumdb: Add option --analyze-in-stages

Add vacuumdb option --analyze-in-stages which runs ANALYZE three times
with different configuration settings, adopting the logic from the
analyze_new_cluster.sh script that pg_upgrade generates.  That way,
users of pg_dump/pg_restore can also use that functionality.

Change pg_upgrade to create the script so that it calls vacuumdb instead
of implementing the logic itself.
psql: conditionally display oids and replication identity

In psql \d+, display oids only when they exist, and display replication
identity only when it is non-default.  Also document the defaults for
replication identity for system and non-system tables.  Update
regression output.
merge master