(gh-33) Configure openbox_boostrap as a puppet_library bolt plugin

This is for OpenVoxProject/openbolt#44 to replace puppet_agent with
openvox_bootstrap as the default puppet_library plugin so that
apply_prep calls install openvox instead of the perforce agent. The
plugin configuration tells bolt what task to execute for this hook, per
https://help.puppet.com/bolt/current/topics/writing_plugins.htm#plugin-hooks

Author: jpartlow

bolt_plugin.json

@@ -0,0 +1,5 @@
+{
+  "hooks": {
+    "puppet_library": { "task": "openvox_bootstrap::install" }
+  }
+}