Don't run travis on 3.1 for now

hadley · hadley · commit d17c346e3d75 · 2018-04-27T10:53:59.000-05:00
diff --git a/.travis.yml b/.travis.yml
@@ -9,7 +9,7 @@ addons:
       - libfreetype6
 
 r:
-- 3.1
+# - 3.1 # because of tidyr <- tidyselect
 - 3.2
 - oldrel
 - release
