Drop unsupported versions of Python and Django, and use graphql-core v3

.travis.yml

@@ -15,18 +15,6 @@ after_success:
 matrix:
   fast_finish: true
   include:
-    - python: 2.7
-      env: DJANGO=1.11
-
-    - python: 3.5
-      env: DJANGO=1.11
-    - python: 3.5
-      env: DJANGO=2.0
-    - python: 3.5
-      env: DJANGO=2.1
-    - python: 3.5
-      env: DJANGO=2.2
-
     - python: 3.6
       env: DJANGO=1.11
     - python: 3.6

setup.py

@@ -16,11 +16,11 @@ rest_framework_require = ["djangorestframework>=3.6.3"]
 tests_require = [
     "pytest>=3.6.3",
     "pytest-cov",
+    "pytest-asyncio",
     "coveralls",
     "mock",
     "pytz",
-    "django-filter<2;python_version<'3'",
-    "django-filter>=2;python_version>='3'",
+    "django-filter>=2",
     "pytest-django>=3.3.2",
 ] + rest_framework_require
 
@@ -45,20 +45,17 @@ setup(
         "Development Status :: 3 - Alpha",
         "Intended Audience :: Developers",
         "Topic :: Software Development :: Libraries",
-        "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 :: Implementation :: PyPy",
     ],
     keywords="api graphql protocol rest relay graphene",
     packages=find_packages(exclude=["tests"]),
     install_requires=[
         "six>=1.10.0",
-        "graphene>=2.1.3,<3",
-        "graphql-core>=2.1.0,<3",
+        "graphene>=3.0.dev,<4",
+        "graphql-core>=3.0.0b0,<4",
         "Django>=1.11",
         "singledispatch>=3.4.0.3",
         "promise>=2.1",

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 envlist =
-    py{27,35,36,37}-django{111,20,21,22,master},
+    py{36,37}-django{111,20,21,22,master},
     black,flake8
 
 [travis:env]
@@ -18,7 +18,7 @@ setenv =
     DJANGO_SETTINGS_MODULE=django_test_settings
 deps =
     -e.[test]
-    psycopg2
+    psycopg2-binary
     django111: Django>=1.11,<2.0
     django20: Django>=2.0,<2.1
     django21: Django>=2.1,<2.2