Travis has released Xenial support (encode#6322)

Author: rpkilby

.travis.yml

@@ -1,5 +1,6 @@
 language: python
 cache: pip
+dist: xenial
 
 sudo: false
 
@@ -21,15 +22,15 @@ matrix:
       - { python: "3.6", env: DJANGO=2.1 }
       - { python: "3.6", env: DJANGO=master }
 
-      - { python: "3.7", env: DJANGO=2.0, dist: xenial, sudo: true }
-      - { python: "3.7", env: DJANGO=2.1, dist: xenial, sudo: true }
-      - { python: "3.7", env: DJANGO=master, dist: xenial, sudo: true }
+      - { python: "3.7", env: DJANGO=2.0 }
+      - { python: "3.7", env: DJANGO=2.1 }
+      - { python: "3.7", env: DJANGO=master }
 
-      - { python: "3.6", env: TOXENV=base }
+      - { python: "3.7", env: TOXENV=base }
       - { python: "2.7", env: TOXENV=lint }
       - { python: "2.7", env: TOXENV=docs }
 
-      - python: "3.6"
+      - python: "3.7"
         env: TOXENV=dist
         script:
           - python setup.py bdist_wheel