Drop support for Python 3.4, add support for Python 3.8.

.travis.yml

@@ -2,10 +2,10 @@ language: python
 dist: xenial
 python:
   - "2.7"
-  - "3.4"
   - "3.5"
   - "3.6"
   - "3.7"
+  - "3.8-dev"
 services:
   - postgresql
 before_install:

CHANGES.rst

@@ -4,7 +4,9 @@ Changes
 1.2 (unreleased)
 ----------------
 
-* Add support for Python 3.7
+* Drop support for Python 3.4.
+
+* Add support for Python 3.7 and 3.8.
 
 * Fix deprecation warnings for the event system. We already used it in general
   but still leveraged the old extenion mechanism in some places.

setup.py

@@ -30,10 +30,10 @@
         "Programming Language :: Python :: 2",
         "Programming Language :: Python :: 2.7",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.4",
         "Programming Language :: Python :: 3.5",
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
+        "Programming Language :: Python :: 3.8",
         "License :: OSI Approved :: Zope Public License",
         "Topic :: Software Development :: Libraries :: Python Modules",
     ],

tox.ini

@@ -1,10 +1,10 @@
 [tox]
 envlist =
     py27,
-    py34,
     py35,
     py36,
     py37,
+    py38,
 # pypy fails because of some weird test error that might be an issue with
 # sqlalchemy, pypy, and issues with object identity.