docs(examples): add README for examples directory

Closes #1511

examples/README.md

@@ -0,0 +1,19 @@
+## Examples of using hyper
+
+Run examples with `cargo run --example example_name`.
+
+### Available examples
+
+* [`client`](client.rs) - A simple CLI http client that request the url passed in parameters and outputs the response content and details to the stdout, reading content chunk-by-chunk.
+
+* [`echo`](echo.rs) - An echo server that copies POST request's content to the response content.
+
+* [`hello`](hello.rs) - A simple server that returns "Hello World!" using a closure wrapped to provide a [`Service`](../src/service/service.rs).
+
+* [`multi_server`](multi_server.rs) - A server that listens to two different ports, a different [`Service`](../src/service/service.rs) by port, spawning two [`futures`](../src/rt.rs).
+
+* [`params`](params.rs) - A webserver that accept a form, with a name and a number, checks the parameters are presents and validates the input.
+
+* [`send_file`](send_file.rs) - A server that sends back content of files either simply or streaming the response.
+
+* [`web_api`](web_api.rs) - A server consisting in a service that returns incoming POST request's content in the response in uppercase and a service that call that call the first service and includes the first service response in its own response.