Release 1.3.3

HISTORY.md

+## 1.3.3 (2015-02-17)
+
+* Address a slight typo with `POSIX` [#456](https://github.com/github/markup/pull/456)
+
+[Full changelog](https://github.com/github/markup/compare/v1.3.2...v1.3.3)
+
 ## 1.3.2 (2015-02-17)
 * RST: Output code instead of tt for inline literals [#370](https://github.com/github/markup/pull/370)

lib/github-markup.rb

 module GitHub
   module Markup
-    VERSION = '1.3.2'
+    VERSION = '1.3.3'
     Version = VERSION
   end
 end