Fixed SSL support on the httpd component, and also on the EiffelWeb standalone connector.

- the standalone connector support for SSL, is using certicate files for now (no in-memory support).
  - to enable ssl support, set ecf variable `httpd_ssl_enabled=true`.
  - added the `simple_ssl` example to demonstrate how to have standalone ssl server.
    (be careful when using EiffelNet SSL and the http_client library, disable the libcurl
      via ecf variable `libcurl_http_client_disabled=true` )

Added support for recv timeout to the EiffelWeb standalone connector.
  - made EiffelWeb compilable with 16.05 and upcoming 16.11.
    Done via ecfs condition on version to accept EiffelNet with recv_timeout (from 16.11), and without (until 16.05).
  - adding recv timeout prevents server to hang for ever if a client wait too long to send data.

Updated various comments.

examples/simple_ssl/simple.crt

@@ -0,0 +1,15 @@
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+pEwr7CGEatBFTMkwDAYDVR0TBAUwAwEB/zANBgkqhkiG9w0BAQUFAAOBgQAi+h4/
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+zQ6jCLXfyD/tvemB+yYEI3NntvRKx5/zt6Q26Q==
+-----END CERTIFICATE-----