Speed up COPY into tables with DEFAULT nextval()

Previously the presence of a nextval() prevented the
use of batch-mode COPY.  This patch introduces a
special case just for nextval() functions. In future
we will introduce a general case solution for
labelling volatile functions as safe for use.
Fix typo in comment.

Sawada Masahiko
Fix to_timestamp/to_date's handling of consecutive spaces in format string.

When there are consecutive spaces (or other non-format-code characters) in
the format, we should advance over exactly that many characters of input.
The previous coding mistakenly did a "skip whitespace" action between such
characters, possibly allowing more input to be skipped than the user
intended.  We only need to skip whitespace just before an actual field.

This is really a bug fix, but given the minimal number of field complaints
and the risk of breaking applications coded to expect the old behavior,
let's not back-patch it.

Jeevan Chalke
Remove pg_stat_statements--1.1.sql.

Commit 91484409bdd17f330d10671d388b72d4ef1451d7 should have removed this
file, not just reduced it to zero size.
Expose a routine to print triggers during EXPLAIN ANALYZE

This is so that auto_explain can use it.

Kyotaro HORIGUCHI
Merge branch 'master' of git://git.postgresql.org/git/postgresql
Merge branch 'master' into invtrans
fixed up whitespace issues flagged up by git diff --check
Re-sequenced OIDs for inverse transition functions

I had previously run out of the original range that I had picked for these and I ended up spilling over to 8000 due to lack of a working unused_oids perl script on windows. I've since checked which OIDs are free on a linux box's unused_oids script. It looks like 32xx seem like a nice choice for inverse transition functions. Perhaps this will change later, but my use of 80xx was rather obscure, so it seems like a good idea to put these at something half realistic.
Merge branch 'invtrans' of https://github.com/david-rowley/postgres into invtrans
Forgot to specify the inverse transition function for string_agg(bytea) in pg_aggregate.h
Tried to massage the explanation of the expanded STRICT and NULL
behaviour of aggreages with inverse transition functions into the
existing description these cases for aggregates without inverse
transition functions.