Don't VALGRIND_PRINTF() each query string.

Doing so was helpful for some Valgrind usage and distracting for other
usage.  One can achieve the same effect by changing log_statement and
pointing both PostgreSQL and Valgrind logging to stderr.

Per gripe from Andres Freund.
intarray:  return empty zero-dimensional array for an empty array

Previously a one-dimensional empty array was returned, but its text
representation matched a zero-dimensional array, and there is no way to
dump/reload a one-dimensional empty array.

BACKWARD INCOMPATIBILITY

Per report from elein
Close file to no leak file descriptor memory. Found by Coverity.
Return error if allocation of new element was not possible.

Found by Coverity.
Introduce InvalidCommandId.

This allows a 32-bit field to represent an *optional* command ID
without a separate flag bit.

Andres Freund
Show schemas in information_schema.schemata that the current has access to

Before, it would only show schemas that the current user owns.  Per
discussion, the new behavior is more useful and consistent for PostgreSQL.
Remove leftover function prototype.

The prototype for inval_twophase_postcommit wasn't removed when it's definition
was removed in efc16ea520679d713d98a2c7bf1453c4ff7b91ec / the initial HS commit.

Andres Freund
psql: honor 'footer' option for expanded output

"No rows" previously only honored the tuples-only option.

Per report from Eli Mesika
psql: fix \copy stdin trailing space requirement

Previously a trailing space was required for \copy ... stdin:

	copy foo from stdin ;

Etsuro Fujita
Add comment for VARSIZE_ANY_EXHDR macro

Gurjeet Singh
docs:  Update libpq and testlo examples

Josh Kupershmidt
fuzzystrmatch: replace broken link in C comment

Albe Laurenz
Create index on srt table in citext regression tests.

Comments and the tests make clear that the intent is to test with
and without an index, but there was no index.
Ignore interrupts during quickdie().

Once the administrator has called for an immediate shutdown or a backend
crash has triggered a reinitialization, no mere SIGINT or SIGTERM should
change that course.  Such derailment remains possible when the signal
arrives before quickdie() blocks signals.  That being a narrow race
affecting most PostgreSQL signal handlers in some way, leave it for
another patch.  Back-patch this to all supported versions.
Fix typos
Add a GUC to report whether data page checksums are enabled.

Bernd Helmle
Rename various "freeze multixact" variables

It seems to make more sense to use "cutoff multixact" terminology
throughout the backend code; "freeze" is associated with replacing of an
Xid with FrozenTransactionId, which is not what we do for MultiXactIds.

Andres Freund
Some adjustments by Álvaro Herrera
Remove `proc` argument from LockCheckConflicts

This has been unused since commit 8563ccae2caf.

Noted by Antonin Houska
Typo fix.

Etsuro Fujita
Documentation correction.

Etsuro Fujita