py-letsencrypt: Mark as not ready for python-3.x.

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Module Name:	pkgsrc-wip
Committed By:	Thomas Klausner <wiz%NetBSD.org@localhost>
Pushed By:	wiz
Date:		Fri Dec 11 08:27:26 2015 +0100
Changeset:	6df4b06ef73b8a2b6f908381511c466b123e684a

Modified Files:
	py-letsencrypt/Makefile

Log Message:
py-letsencrypt: Mark as not ready for python-3.x.

I see lines like these:
/usr/pkg/bin/python3.3 -O /tmp/tmpvwmv_e.py
  File "/usr/pkg/lib/python3.3/site-packages/letsencrypt/cli.py", line 462
    except errors.PluginSelectionError, e:
                                      ^
SyntaxError: invalid syntax

To see a diff of this commit:
https://wip.pkgsrc.org/cgi-bin/gitweb.cgi?p=pkgsrc-wip.git;a=commitdiff;h=6df4b06ef73b8a2b6f908381511c466b123e684a

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.

diffstat:
 py-letsencrypt/Makefile | 2 ++
 1 file changed, 2 insertions(+)

diffs:
diff --git a/py-letsencrypt/Makefile b/py-letsencrypt/Makefile
index 2630f3b..4d5a4e4 100644
--- a/py-letsencrypt/Makefile
+++ b/py-letsencrypt/Makefile
@@ -8,6 +8,8 @@ LICENSE=	apache-2.0
 
 EGG_NAME=	${DISTNAME}
 
+PYTHON_VERSIONS_INCOMPATIBLE=	33 34 35 # as of 0.1.0
+
 .include "Makefile.common"
 .include "../../lang/python/egg.mk"