This is a simple reimplementation of rbslack extension with the integration framework. This allow multiple instance of the integration, with different configuration for different channels. A custom form and template is also added for the configure integration page.
Additionally, it also allow the user to configure the integration such that the channel will only receive notification if the review request is intended for the selected groups.
Lastly, the integration can be configure to target a local site. Notification will only be send to Slack if the review belongs to the particular local site.

Manual testing with different configuration and different review's update.

No local site and group
Target a single group
Target multiple groups
Local site
Local site with groups
Multiple Slack integration.