pgsql: Fix TAP tests and MSVC scripts for pathnames with spaces.

Fix TAP tests and MSVC scripts for pathnames with spaces.

Change assorted places in our Perl code that did things like
    system("prog $path/file");
to do it more like
    system('prog', "$path/file");
which is safe against spaces and other special characters in the path
variable.  The latter was already the prevailing style, but a few bits
of code hadn't gotten this memo.  Back-patch to 9.4 as relevant.

Michael Paquier, Kyotaro Horiguchi

Discussion: <20160704.160213.111134711.horiguchi.kyotaro@lab.ntt.co.jp>

Branch
------
REL9_5_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/f80395ca1f95dde1d5e0eabcab148b3645bcb6ec

Modified Files
--------------
src/tools/msvc/Install.pm   | 32 ++++++++++++++++++++++----------
src/tools/msvc/vcregress.pl | 20 +++++++++++++-------
2 files changed, 35 insertions(+), 17 deletions(-)