check for the folling headers:
* `X-Gitlab-Token``
* `Content-Type`

check for the following query parameterts:
* `room`

Enable wiki events

They appear to work

Fixes #16

Add pipelines and wiki pages and update dependencies

Fixes #7
Fixes #3

The webhook library maintainer preferred having a separate type for
confidential issues.

This won't work without go-playground/webhooks#18

* Add shorthand for issue creating (!gitlab create ...)