(Deepfence) Understand Integrations with other external systems (feature #5)

We need to write full documentation for the following points:

**Integrations with:** 
- SIEM 
- Notification Channels  

**Ticketing:** 
Ready to use integrations with 
- Slack 
- PagerDuty 
- HTTP endpoint 
- Jira 
- Splunk 
- ELK 
- Sumo Logic 
- Amazon S3.