examples/manuals: Improve/update ns-related documentation

* example config files with current libosmogb options
* Include NS2-related configuration chapters in manual

Closes: SYS#5115
Change-Id: I57cf5dc4ee686352252086917f5f63d5a69dddd7
diff --git a/doc/examples/osmo-gbproxy/osmo-gbproxy-pool.cfg b/doc/examples/osmo-gbproxy/osmo-gbproxy-pool.cfg
index bbc8a1b..7457ee8 100644
--- a/doc/examples/osmo-gbproxy/osmo-gbproxy-pool.cfg
+++ b/doc/examples/osmo-gbproxy/osmo-gbproxy-pool.cfg
@@ -7,22 +7,25 @@
 !
 gbproxy
   nri bitlen 4
-  nri null add 0 4
+  nri null add 15
 sgsn nsei 101
  name main
  nri add 1
- nri add 11
 sgsn nsei 102
  nri add 2
- nri add 12
 ns
- bind udp local
-  listen 127.0.0.100 23000
-  accept-ipaccess
+ bind udp sgsn-side
+  listen 127.0.0.1 23000
  nse 101
-  nsvc ipa local 192.168.100.239 7777 nsvci 101
+  ip-sns-bind sgsn-side
+  ip-sns-remote 127.0.1.1 23000
  nse 102
-  nsvc ipa local 192.168.100.239 7778 nsvci 102
+  ip-sns-bind sgsn-side
+  ip-sns-remote 127.0.1.2 23000
+ bind udp bss-side
+  listen 127.0.0.100 23000
+  accept-dynamic-ip-sns
+ ip-sns-default bind bss-side
  timer tns-block 3
  timer tns-block-retries 3
  timer tns-reset 3