[mod_python3, ESL py3mod] Add Python3 support.

libs/esl/python3/python-config

@@ -0,0 +1,55 @@
+#!/usr/bin/env python3
+
+from __future__ import print_function
+import sys
+import os
+import getopt
+from distutils import sysconfig
+
+valid_opts = ['prefix', 'exec-prefix', 'includes', 'libs', 'cflags', 
+              'ldflags', 'help']
+
+def exit_with_usage(code=1):
+    print("Usage: %s [%s]" % (sys.argv[0], '|'.join('--'+opt for opt in valid_opts)), file=sys.stderr)
+    sys.exit(code)
+
+try:
+    opts, args = getopt.getopt(sys.argv[1:], '', valid_opts)
+except getopt.error:
+    exit_with_usage()
+
+if not opts:
+    exit_with_usage()
+
+opt = opts[0][0]
+
+pyver = sysconfig.get_config_var('LDVERSION')
+if pyver == None:
+    pyver = sysconfig.get_config_var('VERSION')
+getvar = sysconfig.get_config_var
+
+if opt == '--help':
+    exit_with_usage(0)
+
+elif opt == '--prefix':
+    print(sysconfig.PREFIX)
+
+elif opt == '--exec-prefix':
+    print(sysconfig.EXEC_PREFIX)
+
+elif opt in ('--includes', '--cflags'):
+    flags = ['-I' + sysconfig.get_python_inc(),
+             '-I' + sysconfig.get_python_inc(plat_specific=True)]
+    if opt == '--cflags':
+        flags.extend(getvar('CFLAGS').split())
+    print(' '.join(flags))
+
+elif opt in ('--libs', '--ldflags'):
+    libs = getvar('LIBS').split() + getvar('SYSLIBS').split()
+    libs.append('-lpython'+pyver)
+    # add the prefix/lib/pythonX.Y/config dir, but only if there is no
+    # shared library in prefix/lib/.
+    if opt == '--ldflags' and not getvar('Py_ENABLE_SHARED'):
+        libs.insert(0, '-L' + getvar('LIBPL'))
+    print(' '.join(libs))
+