Merge pull request #523 from enricosada/allow_failures_on_mono_latest

allow failures on mono latest

Author: dsyme

.travis.yml

@@ -20,3 +20,7 @@ script:
   - xbuild ./src/fsharp-library-unittests-build.proj /p:TargetFramework=net40 /p:Configuration=Release
   - (cd tests/projects; ./build.sh)
   - (cd tests/fsharp/core; ./run-opt.sh)
+
+matrix:
+  allow_failures:
+    - mono: latest