travis: switch to xenial build env

In principle we'd like everything to work with ancient versions. In
practice someone needs drive that effort.

diff --git a/.travis.yml b/.travis.yml
index 79802b7b1234aea09ad9dc1cfc3eeddea72ba446..a2caf010fdec7ab8de6fadb7e5bb938099fa5858 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,6 @@
 language: c
 
-dist: trusty
-sudo: false
+dist: xenial
 
 addons:
   apt: