doc: add more public datasets

Add:
- UNSW-NB15
- CIC-IDS2017
- CSE-CIC-IDS2018
- CIC-DDoS2019

Update formatting for better display.

(cherry picked from commit 66473f6ad7)

doc/userguide/public-data-sets.rst

@@ -1,18 +1,41 @@
-Public Data Sets
-================
+Public Datasets (PCAPs)
+=======================
 
-Collections of pcaps for testing and profiling.
+Collections of public datasets and packet captures for testing and
+profiling. Not to be confused with Suricata ``datasets``.
 
-DARPA sets: https://www.ll.mit.edu/r-d/datasets?author=All&rdarea=All&rdgroup=All&keywords=cyber&tag=All&items_per_page=10
+`MIT Lincoln Laboratory <https://www.ll.mit.edu/r-d/datasets?keywords=cyber>`__
+   Cyber-focused datasets from MIT, including DARPA datasets.
 
-MAWI sets (pkt headers only, no payloads): http://mawi.wide.ad.jp/mawi/samplepoint-F/2012/
+`MAWI Samplepoint-F <http://mawi.wide.ad.jp/mawi/samplepoint-F/2012/>`__
+   WIDE transit-link traces (packet headers only; no payloads).
 
-MACCDC: http://www.netresec.com/?page=MACCDC
+`MACCDC <http://www.netresec.com/?page=MACCDC>`__
+   Mid-Atlantic Collegiate Cyber Defense Competition traffic captures.
 
-Netresec: http://www.netresec.com/?page=PcapFiles
+`Netresec <http://www.netresec.com/?page=PcapFiles>`__
+   Public pcap files for network forensics and malware analysis.
 
-Wireshark: https://gitlab.com/wireshark/wireshark/-/wikis/SampleCaptures
+`Wireshark Sample Captures <https://gitlab.com/wireshark/wireshark/-/wikis/SampleCaptures>`__
+   Curated sample captures useful for protocol testing.
 
-Security Onion collection: https://docs.securityonion.net/en/2.4/pcaps.html
+`Security Onion PCAP collection <https://docs.securityonion.net/en/2.4/pcaps.html>`__
+   Collection of links and downloads for lab datasets.
 
-Stratosphere IPS. Malware Capture Facility Project: https://stratosphereips.org/category/dataset.html
+`Stratosphere IPS Malware Capture Facility <https://stratosphereips.org/category/dataset.html>`__
+   Malware-oriented captures with related dataset material.
+
+`UNSW-NB15 <https://research.unsw.edu.au/projects/unsw-nb15-dataset>`__
+   UNSW Cyber Range dataset with IXIA-generated benign/attack traffic,
+   raw pcap captures, and labeled flow-feature CSV files.
+
+`CIC-IDS2017 <https://www.unb.ca/cic/datasets/ids-2017.html>`__
+   Intrusion Detection Evaluation Dataset
+
+`CSE-CIC-IDS2018 <https://www.unb.ca/cic/datasets/ids-2018.html>`__
+   CSE-CIC-IDS2018 on AWS: A collaborative project between the
+   Communications Security Establishment (CSE) & the Canadian
+   Institute for Cybersecurity (CIC).
+
+`CIC-DDoS2019 <https://www.unb.ca/cic/datasets/ddos-2019.html>`__
+   Dataset containing DDoS attacks resembling true real world data.