Fix travis idiosyncrasy

That travis stuff docu is just unuseful.

diff --git a/.travis.yml b/.travis.yml
index 245451b..db99970 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,6 +7,8 @@ compiler:
   - clang
 addons:
   apt:
+    sources:
+      - bionic
     packages:
       - autoconf
       - automake