Thin AP: manage from the WebUI

Thin AP are nebulous objects in the database: they are added automatically from the controller they are discovered on, but there is no way to manage them more directly, e.g. to suppress alerts on specific AP through the use of custom properties.

Idea:

- allow management of Thin AP through the WebUI

- include the ability to set custom properties on Thin AP

- include the ability to delete a ThinAP (recognizing that it may be rediscovered and re-added)

- generation of alerts on specific AP