mod_http_oauth2: Correctly verify OAuth client credentials on revocation Makes no sense to validate against username and password here, or using a token to revoke another token, or itself? In fact, upon further discussion, why do you need credentials to revoke a token? If you are not supposed to have the token, revoking it seems the most responsible thing to do with it, so it should be allowed, while if you are supposed to have it, you should be allowed to revoke it.

Over the years, some servers stop working for various reasons, and leave
behind broken roster subscriptions that trigger failing s2s connections.
This module allows cleaning up such cases by unsubscribing local users
from their contacts on those servers. Also works for typos and the like.
Use with care.

```lua
Component "gmail.com" "unsubscriber"
```