Update spring to version 1.5.0

Author: sferik

Gemfile.lock

@@ -192,7 +192,7 @@ GEM
     simplecov-html (0.10.0)
     skylight (0.9.4)
       activesupport (>= 3.0.0)
-    spring (1.4.4)
+    spring (1.5.0)
     sprockets (3.4.1)
       rack (> 1, < 3)
     sprockets-rails (2.3.3)