Merge pull request linode#59 from jsager/changelog-09-24

Added API 4.0.6 changelog

Author: Josh Sager

content/changelog/2018/09-24.md

@@ -0,0 +1,11 @@
+---
+title: "4.0.6: 2018-09-24"
+date: "2018-09-24T11:02:00-04:00"
+description: "API Changelog 4.0.6"
+changelog:
+- API
+version: 4.0.6
+---
+### Added
+* Added closeable support tickets via /support/tickets/:id/close
+  * Only applies to tickets that are closeable