MINOR: contrib/spoa_server: Add random IP score

The example configuration uses sess.ip_score however this variable
is not referenced within the example scripts.  This patch adds support
for sess.ip_score to the python + lua scripts and generates a
random number between 1 and 100.
diff --git a/contrib/spoa_server/ps_lua.lua b/contrib/spoa_server/ps_lua.lua
index 2662045..4d1fc52 100644
--- a/contrib/spoa_server/ps_lua.lua
+++ b/contrib/spoa_server/ps_lua.lua
@@ -1,4 +1,5 @@
 require("print_r")
+require("math")
 
 print_r("Load lua message processors")
 
@@ -14,4 +15,5 @@
 	spoa.set_var_ipv6("ipv6", spoa.scope.txn, "1::f")
 	spoa.set_var_str("str", spoa.scope.txn, "1::f")
 	spoa.set_var_bin("bin", spoa.scope.txn, "1::f")
+	spoa.set_var_int32("ip_score", spoa.scope.sess, math.random(100))
 end)