Express example doc

Signed-off-by: Fabio José <fabiojose@gmail.com>

examples/express-ex/README.md

@@ -0,0 +1,35 @@
+# Express Example
+
+## To Start
+
+```bash
+npm start
+```
+
+## To Post an Event
+
+__A Structured One__
+
+```bash
+curl -X POST \
+     -d'@../payload/v02/structured-event-0.json' \
+     -H'Content-Type:application/cloudevents+json' \
+     http://localhost:3000/
+```
+
+__A Binary One__
+
+```bash
+curl -X POST \
+     -d'@../payload/data-0.json' \
+     -H'Content-Type:application/json' \
+     -H'ce_specversion:0.2' \
+     -H'ce_type:com.github.pull.create' \
+     -H'ce_source:https://github.com/cloudevents/spec/pull/123' \
+     -H'ce_id:45c83279-c8a1-4db6-a703-b3768db93887' \
+     -H'ce_time:2019-06-21T17:31:00Z' \
+     http://localhost:3000/
+```
+__A Batch One__
+
+TODO