Fix some travis config issues

Author: davesque

.travis.yml

@@ -1,14 +1,15 @@
 language: python
 
+dist: xenial
+sudo: required
+
 cache: pip
 
 python:
     - "2.7"
-    - "3.4"
     - "3.5"
     - "3.6"
-
-sudo: false
+    - "3.7"
 
 env:
     - DJANGO=1.11
@@ -22,18 +23,20 @@ matrix:
       - python: "3.6"
         env: TOXENV="lint"
     exclude:
+      - python: "3.7"
+        env: DJANGO=1.11
       - python: "2.7"
         env: DJANGO=2.0
       - python: "2.7"
         env: DJANGO=2.1
+      - python: "3.5"
+        env: DJANGO=2.1
       - python: "2.7"
         env: DJANGO=master
-      - python: "3.4"
-        env: DJANGO=master
-      - python: "3.4"
-        env: DJANGO=2.1
       - python: "3.5"
         env: DJANGO=master
+      - python: "3.6"
+        env: DJANGO=master
     allow_failures:
       - env: DJANGO=master
 

tox.ini

@@ -5,7 +5,8 @@ addopts=--tb=short
 envlist =
        py{27,35,36}-django111-drf{35,36,37,38},
        py{35,36,37}-django20-drf{37,38},
-       py37-django{21,master}-drf{38,39},
+       py{36,37}-django21-drf{38,39},
+       py37-djangomaster-drf39,
        lint
 
 [travis:env]