added sql/ip-pool-db scenario

testing/tests/sql/ip-pool-db/description.txt

@@ -0,0 +1,10 @@
+The roadwarriors <b>carol</b> and <b>dave</b> set up a connection each 
+to gateway <b>moon</b>. The authentication is based on <b>X.509 certificates</b>.
+Both <b>carol</b> and <b>dave</b> request a <b>virtual IP</b> via the IKEv2 configuration
+payload. The gateway moon assigns virtual IP addresses from a pool named <b>bigpool</b>
+predefined in the SQL database. 
+<p>
+Upon the successful establishment of the IPsec tunnels, automatically inserted
+iptables-based firewall rules let pass the tunneled traffic.
+In order to test both tunnel and firewall, both <b>carol</b> and <b>dave</b> ping
+the client <b>alice</b> behind the gateway <b>moon</b>.