Put latest version in the readme

Peter Arentsen · Peter Arentsen · commit e03a5a0cd210 · 2017-10-21T01:55:18.000+02:00
diff --git a/README.md b/README.md
@@ -11,7 +11,7 @@ Add the dependency to your mix file:
 # mix.exs
 defp deps do
   […,
-   {:liquid, "~> 0.4.0"}]
+   {:liquid, "~> 0.8.0"}]
 end
 ```
 
