MINOR/DOC: spoe-server: Add documentation

This is the documentation and examples.
diff --git a/contrib/spoa_server/spoa-server.conf b/contrib/spoa_server/spoa-server.conf
new file mode 100644
index 0000000..13bd126
--- /dev/null
+++ b/contrib/spoa_server/spoa-server.conf
@@ -0,0 +1,33 @@
+global
+	debug
+
+defaults
+	mode http
+	option httplog
+	option dontlognull
+	timeout connect 5000
+	timeout client 5000
+	timeout server 5000
+
+listen test
+	mode http
+	bind :10001
+	filter spoe engine spoa-server config spoa-server.spoe.conf
+	http-request set-var(req.a) var(txn.iprep.null),debug
+	http-request set-var(req.a) var(txn.iprep.boolean),debug
+	http-request set-var(req.a) var(txn.iprep.int32),debug
+	http-request set-var(req.a) var(txn.iprep.uint32),debug
+	http-request set-var(req.a) var(txn.iprep.int64),debug
+	http-request set-var(req.a) var(txn.iprep.uint64),debug
+	http-request set-var(req.a) var(txn.iprep.ipv4),debug
+	http-request set-var(req.a) var(txn.iprep.ipv6),debug
+	http-request set-var(req.a) var(txn.iprep.str),debug
+	http-request set-var(req.a) var(txn.iprep.bin),debug
+	http-request redirect location /%[var(sess.iprep.ip_score)]
+
+backend spoe-server
+	mode tcp
+	balance roundrobin
+	timeout connect 5s
+	timeout server  3m
+	server spoe-server 127.0.0.1:12345