Add link WIP changelog for 0.5 and titles for 0.5.x

[skip ci]

Author: elia

CHANGELOG.md

@@ -1,5 +1,14 @@
 ## edge
 
+## 0.5.5 2013-11-25
+## 0.5.4 2013-11-20
+## 0.5.3 2013-11-12
+## 0.5.2 2013-11-11
+## 0.5.1 2013-11-10
+## 0.5.0 2013-11-03
+
+*   WIP: https://gist.github.com/elia/7747460
+
 ## 0.4.2 2013-07-03
 
 *   Added `Kernel#rand`. (fntzr)