Upgrade sringio

Author: rafaelfranca

Gemfile.lock

@@ -232,7 +232,7 @@ GEM
       net-scp (>= 1.1.2)
       net-sftp (>= 2.1.2)
       net-ssh (>= 2.8.0)
-    stringio (3.1.1)
+    stringio (3.1.7)
     thor (1.3.1)
     tilt (2.0.11)
     timeout (0.4.1)