travisci: Test Python 3.7 as well

Use the workaround from

    https://github.com/travis-ci/travis-ci/issues/9815

since Python 3.7 is not yet supported by the default image.

diff --git a/.travis.yml b/.travis.yml
index bf95addb5131ad3483fe8ec0b2eb5e069b892005..9eee95c80fcd491f773363d66c8fe0a1ab37d58d 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,6 +9,11 @@ python:
   - "3.4"
   - "3.5"
   - "3.6"
+matrix:
+  include:
+    - python: 3.7
+      dist: xenial
+      sudo: true
 
 before_install:
   - sudo apt-get -qq update