Add 'tap_tests' flag in config_default.pl

This makes the flag more visible for testers using the default file as a
template, increasing the likelyhood that the test suite will be run.
Also have the flag be displayed in the fake "configure" output, if set.

This patch is two new lines only, but perltidy decides to shift things
around which makes it appear a bit bigger.

Author: Michaël Paquier
Reviewed-by: Craig Ringer
Discussion: https://www.postgresql.org/message-id/CAB7nPqRet6UAP2APhZAZw%3DVhJ6w-Q-gGLdZkrOqFgd2vc9-ZDw%40mail.gmail.com

src/tools/msvc/Solution.pm

@@ -643,6 +643,7 @@ sub GetFakeConfigure
 	$cfg .= ' --enable-integer-datetimes'
 	  if ($self->{options}->{integer_datetimes});
 	$cfg .= ' --enable-nls' if ($self->{options}->{nls});
+	$cfg .= ' --enable-tap-tests' if ($self->{options}->{tap_tests});
 	$cfg .= ' --with-ldap'  if ($self->{options}->{ldap});
 	$cfg .= ' --without-zlib' unless ($self->{options}->{zlib});
 	$cfg .= ' --with-extra-version' if ($self->{options}->{extraver});

src/tools/msvc/config_default.pl

@@ -16,6 +16,7 @@ our $config = {
 	ldap      => 1,        # --with-ldap
 	extraver  => undef,    # --with-extra-version=<string>
 	nls       => undef,    # --enable-nls=<path>
+	tap_tests => undef,    # --enable-tap-tests
 	tcl       => undef,    # --with-tls=<path>
 	perl      => undef,    # --with-perl
 	python    => undef,    # --with-python=<path>