Enable transforms modules to build and run with Mingw builds.

These modules were all missing essential Windows scaffolding, including
resources files and descriptions, and links to the relevant library
import files. This latter item means that the modules can't be built
with pgxs on Windows, as we don't install the import files. If we ever
decide to install them this restriction could probably be removed.

Also, as with plperl we need to make sure that perl's CORE directory is
last on the include list, as on Windows it appears to contain some
headers with names that clash with names of some headers we include.

contrib/hstore_plperl/Makefile

 # contrib/hstore_plperl/Makefile
 
 MODULE_big = hstore_plperl
-OBJS = hstore_plperl.o
+OBJS = hstore_plperl.o $(WIN32RES)
+PGFILEDESC = "hstore_plperl - hstore transform for plperl"
 
-PG_CPPFLAGS = -I$(top_srcdir)/src/pl/plperl -I$(top_srcdir)/contrib/hstore -I$(perl_archlibexp)/CORE
+PG_CPPFLAGS = -I$(top_srcdir)/src/pl/plperl -I$(top_srcdir)/contrib/hstore
 
 EXTENSION = hstore_plperl hstore_plperlu
 DATA = hstore_plperl--1.0.sql hstore_plperlu--1.0.sql
@@ -22,7 +23,15 @@ include $(top_builddir)/src/Makefile.global
 include $(top_srcdir)/contrib/contrib-global.mk
 endif
 
-# see plperl
 ifeq ($(PORTNAME), win32)
+# these settings are the same as for plperl
 override CPPFLAGS += -DPLPERL_HAVE_UID_GID -Wno-comment
+# This means we need an in-tree build on Windows, not a pgxs build
+SHLIB_LINK += ../hstore/libhstore.a $(wildcard ../../src/pl/plperl/libperl*.a)
 endif
+
+# As with plperl we need to make sure that the CORE directory is included
+# last, probably because it sometimes contains some header files with names
+# that clash with some of ours, or with some that we include, notably on
+# Windows.
+override CPPFLAGS := $(CPPFLAGS) -I$(perl_archlibexp)/CORE

contrib/hstore_plpython/Makefile

 # contrib/hstore_plpython/Makefile
 
 MODULE_big = hstore_plpython$(python_majorversion)
-OBJS = hstore_plpython.o
+OBJS = hstore_plpython.o $(WIN32RES)
+PGFILEDESC = "hstore_plpython - hstore transform for plpython"
 
 PG_CPPFLAGS = -I$(top_srcdir)/src/pl/plpython $(python_includespec) -I$(top_srcdir)/contrib/hstore
 
@@ -22,6 +23,11 @@ include $(top_builddir)/src/Makefile.global
 include $(top_srcdir)/contrib/contrib-global.mk
 endif
 
+ifeq ($(PORTNAME), win32)
+# This means we need an in-tree build on Windows, not a pgxs build
+SHLIB_LINK += ../hstore/libhstore.a $(wildcard ../../src/pl/plpython/libpython*.a) $(wildcard ../../src/pl/plpython/libplpython*.a)
+endif
+
 REGRESS_OPTS = --load-extension=hstore
 ifeq ($(python_majorversion),2)
 REGRESS_OPTS += --load-extension=plpythonu --load-extension=hstore_plpythonu

contrib/ltree_plpython/Makefile

 # contrib/ltree_plpython/Makefile
 
 MODULE_big = ltree_plpython$(python_majorversion)
-OBJS = ltree_plpython.o
+OBJS = ltree_plpython.o $(WIN32RES)
+PGFILEDESC = "ltree_plpython - ltree transform for plpython"
 
 PG_CPPFLAGS = -I$(top_srcdir)/src/pl/plpython $(python_includespec) -I$(top_srcdir)/contrib/ltree
 
@@ -22,6 +23,11 @@ include $(top_builddir)/src/Makefile.global
 include $(top_srcdir)/contrib/contrib-global.mk
 endif
 
+ifeq ($(PORTNAME), win32)
+# This means we need an in-tree build on Windows, not a pgxs build
+SHLIB_LINK += $(wildcard ../../src/pl/plpython/libpython*.a)
+endif
+
 REGRESS_OPTS = --load-extension=ltree
 ifeq ($(python_majorversion),2)
 REGRESS_OPTS += --load-extension=plpythonu --load-extension=ltree_plpythonu