Prepare release 3.9.1

CHANGELOG.md

 ## Changelog
 
+### 3.9.1
+  * Various bugfixes in parameter type validation (thanks @craigwatson and @amateo)
+
 ### 3.9.0
   * Bugfix: Fix mismatch between `tls_verify_client` parameter in the eap module manifest and `tls_client` in the eap template (thanks @guest715)
   * Bugfix: Fix users template permits the users array to contain either Hashes or Strings (thanks @guest715)

metadata.json

 {
   "name": "jgazeley-freeradius",
-  "version": "3.9.0",
+  "version": "3.9.1",
   "author": "jgazeley",
   "summary": "Install and configure FreeRADIUS",
   "license": "Apache-2.0",