MSVC: Revert most 9.5 changes to pre-9.5 vcregress.pl tests.

 MSVC: Revert most 9.5 changes to pre-9.5 vcregress.pl tests.
 
 The reverted changes did not narrow the semantic gap between the MSVC
 build system and the GNU make build system.  For targets old and new
 that run multiple suites (contribcheck, modulescheck, tapcheck), restore
 vcregress.pl to mimicking "make -k" rather than the "make -S" default.
 Lack of "-k" would be more burdensome than lack of "-S".  Keep changes
 reflecting contemporary changes to the GNU make build system, and keep
 updates to Makefile parsing.  Keep the loss of --psqldir in "check" and
 "ecpgcheck" targets; it had been a no-op when used alongside
 --temp-install.  No log message mentioned any of the reverted changes.
 Based on a germ by Michael Paquier.  Back-patch to 9.5.