pgsql: Run pg_upgrade and pg_resetxlog with restricted token on Windows

Run pg_upgrade and pg_resetxlog with restricted token on Windows

As with initdb these programs need to run with a restricted token, and
if they don't pg_upgrade will fail when run as a user with Adminstrator
privileges.

Backpatch to all live branches. On the development branch the code is
reorganized so that the restricted token code is now in a single
location. On the stable bramches a less invasive change is made by
simply copying the relevant code to pg_upgrade.c and pg_resetxlog.c.

Patches and bug report from Muhammad Asif Naeem, reviewed by Michael
Paquier, slightly edited by me.

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/fa1e5afa8a26d467aec7c8b36a0b749b690f636c

Modified Files
--------------
contrib/pg_upgrade/pg_upgrade.c       |    3 +
src/bin/initdb/initdb.c               |  170 +----------------------------
src/bin/pg_resetxlog/pg_resetxlog.c   |    3 +
src/common/Makefile                   |    2 +-
src/common/restricted_token.c         |  193 +++++++++++++++++++++++++++++++++
src/include/common/restricted_token.h |   24 ++++
src/test/regress/pg_regress.c         |  105 ++----------------
src/tools/msvc/Mkvcbuild.pm           |    3 +-
8 files changed, 235 insertions(+), 268 deletions(-)