Allow for failures in 3.1 because of startup issues under load

Author: ewoutp

.travis.yml

@@ -15,6 +15,12 @@ env:
 
 script: make $TEST_SUITE
 
+# 3.1 cluster startup is not always a success, causing lots of false positive.
+matrix:
+  allow_failures:
+    - env: TEST_SUITE=run-tests-local-process ARANGODB=arangodb:3.1
+    - env: TEST_SUITE=run-tests-docker        ARANGODB=arangodb:3.1
+
 # Install Docker CE
 before_install:
   - curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -