add intents docs and samples

samples/msg-receiver.lua

@@ -0,0 +1,11 @@
+function on_resume()
+    ui:show_text("empty")
+end
+
+function on_message(value)
+    if type(value) == "table" then
+        ui:show_text("table first element: "..value[1])
+    else
+        ui:show_text(value)
+    end
+end