add sentinel notification plugin doc (#486)

crowdsec-docs/docs/notification_plugins/sentinel.md

@@ -0,0 +1,82 @@
+---
+id: sentinel
+title: Sentinel Plugin
+---
+
+The sentinel plugin is by default shipped with your CrowdSec installation. The following guide shows how to enable it.
+
+## Enabling the plugin:
+
+In your profile file (by default `/etc/crowdsec/profiles.yaml`) , uncomment the section
+```
+#notifications:
+# - sentinel_default 
+```
+
+## Configuring the plugin: 
+
+### Adding the plugin configuration 
+
+By default there would be a sentinel config at `/etc/crowdsec/notifications/sentinel.yaml`.
+You will need to specify:
+ - customer_id
+ - shared_key
+ - log_type 
+
+Example config: 
+
+```yaml
+type: sentinel          # Don't change
+name: sentinel_default  # Must match the registered plugin in the profile
+
+# One of "trace", "debug", "info", "warn", "error", "off"
+log_level: info
+# group_wait:         # Time to wait collecting alerts before relaying a message to this plugin, eg "30s"
+# group_threshold:    # Amount of alerts that triggers a message before <group_wait> has expired, eg "10"
+# max_retry:          # Number of attempts to relay messages to plugins in case of error
+# timeout:            # Time to wait for response from the plugin before considering the attempt a failure, eg "10s"
+
+#-------------------------
+# plugin-specific options
+
+# The following template receives a list of models.Alert objects
+# The output goes in the http request body
+format: |
+  {{.|toJson}}
+
+customer_id: XXX-XXX
+shared_key: XXXXXXX
+log_type: crowdsec
+
+```
+
+**Note** that the `format` is a [go template](https://pkg.go.dev/text/template), which is fed a list of [Alert](https://pkg.go.dev/github.com/crowdsecurity/crowdsec@master/pkg/models#Alert) objects.
+
+### Configuration options
+
+#### customer_id
+
+Also known as the `workspace id`.
+You can get it from the azure portal in `Log Analytics workspace` -> `YOUR_WORKSPACE` -> `Settings` -> `Agents`
+
+#### shared_key
+
+Also known as the `primary key`.
+You can get it from the azure portal in `Log Analytics workspace` -> `YOUR_WORKSPACE` -> `Settings` -> `Agents`
+
+#### log_type
+
+The log type is the name of the log that will be sent to azure.
+
+Assuming you chose `crowdsec`, it will appear as `crowdsec_CL` in azure.
+
+
+## Final Steps:
+
+Let's restart crowdsec
+
+```bash
+sudo systemctl restart crowdsec
+```
+
+You can verify whether the plugin is properly working by triggering scenarios using tools like wapiti, nikto etc. 

crowdsec-docs/sidebars.js

@@ -347,6 +347,7 @@
                     ],
                 },
                 "notification_plugins/email",
+                "notification_plugins/sentinel",
                 "notification_plugins/slack",
                 "notification_plugins/splunk",
                 "notification_plugins/template_helpers",