Changed default ruby to 2.1.9

Dennis Pattmann · Dennis Pattmann · commit 0d5c40d5dd80 · 2017-05-17T14:46:56.000+02:00
diff --git a/.ruby-version b/.ruby-version
@@ -1 +1 @@
-2.3.1
+2.1.9
diff --git a/.travis.yml b/.travis.yml
@@ -2,6 +2,7 @@
 language: ruby
 
 rvm:
+  - 2.1.9
   - 2.3.1
 
 env:

-Original file line number
+Diff line change
 language: ruby
 rvm:
 +  - 2.1.9
   - 2.3.1
 env: