security/py-{acme,certbot}: Make argparse a conditional dependency

Backport an upstream patch [1][2] to setup.py making argparse a conditional
dependency. Without this change, the following error is observed at run-time:

  pkg_resources.DistributionNotFound: The 'argparse' distribution was not found and is required by certbot

This is due to the separate argparse distribution (via PyPI) no longer being
required for Python versions >= 2.7 and >= 3.2, as they contain the argparse
module in the standard library.

Since FreeBSD only supports Python versions with the argparse module built in,
*and* having removed the devel/py-argparse port, the install_requires=argparse
dependency cannot be satisfied, as install_requires is only relevant for non
standard library (PyPI) packages/dependencies.

[1] https://github.com/certbot/certbot/pull/4554
[2] https://github.com/certbot/certbot/issues/4485

PR:		218973
Reported by:	olgeni
Approved by:	koobs (py-certbot, maintainer)
Obtained from:	89af460792
Differential Revision:	https://reviews.freebsd.org/D10546

security/py-acme/Makefile

@@ -3,6 +3,7 @@
 
 PORTNAME=	acme
 PORTVERSION=	0.13.0
+PORTREVISION=	1
 PORTEPOCH=	1
 CATEGORIES=	security python
 MASTER_SITES=	CHEESESHOP

security/py-acme/files/patch-setup.py

@@ -0,0 +1,21 @@
+--- setup.py.orig	2017-04-30 10:29:55 UTC
++++ setup.py
+@@ -8,7 +8,6 @@ version = '0.13.0'
+ 
+ # Please update tox.ini when modifying dependency version requirements
+ install_requires = [
+-    'argparse',
+     # load_pem_private/public_key (>=0.6)
+     # rsa_recover_prime_factors (>=0.8)
+     'cryptography>=0.8',
+@@ -28,6 +27,10 @@ install_requires = [
+     'six',
+ ]
+ 
++# env markers cause problems with older pip and setuptools
++if sys.version_info < (2, 7):
++    install_requires.append('argparse')
++
+ dev_extras = [
+     'nose',
+     'tox',

security/py-certbot/Makefile

@@ -3,6 +3,7 @@
 
 PORTNAME=	certbot
 PORTVERSION=	0.13.0
+PORTREVISION=	1
 PORTEPOCH=	1
 CATEGORIES=	security python
 MASTER_SITES=	CHEESESHOP

security/py-certbot/files/patch-setup.py

@@ -0,0 +1,21 @@
+--- setup.py.orig	2017-04-30 10:33:38 UTC
++++ setup.py
+@@ -36,7 +36,6 @@ version = meta['version']
+ # https://github.com/pypa/pip/issues/988 for more info.
+ install_requires = [
+     'acme=={0}'.format(version),
+-    'argparse',
+     # We technically need ConfigArgParse 0.10.0 for Python 2.6 support, but
+     # saying so here causes a runtime error against our temporary fork of 0.9.3
+     # in which we added 2.6 support (see #2243), so we relax the requirement.
+@@ -56,6 +55,10 @@ install_requires = [
+     'zope.interface',
+ ]
+ 
++# env markers cause problems with older pip and setuptools
++if sys.version_info < (2, 7):
++    install_requires.append('argparse')
++
+ dev_extras = [
+     # Pin astroid==1.3.5, pylint==1.4.2 as a workaround for #289
+     'astroid==1.3.5',